Classic Low Carb Keto Ground Turkey Taco Casserole

Here is my favorite low carb keto ground turkey taco casserole, with seasoned ground turkey, sautéed peppers and onions, plenty of melted cheddar cheese, and all your favorite taco toppings.

This casserole has become our go-to weeknight dinner when we’re craving Mexican food but want to keep things on the healthier side. I love that it’s filling enough to satisfy everyone at the table, and the leftovers reheat beautifully for lunch the next day.

What Kind of Ground Turkey Should I Use?

For this taco casserole, you’ll want to pick up ground turkey from the meat section of your grocery store, and the fat percentage matters more than you might think. I’d recommend using 93/7 or 85/15 ground turkey (that’s the lean-to-fat ratio) since the leaner options can end up a bit dry in a casserole like this. If you can only find the super lean 99/1 ground turkey, just add an extra tablespoon of oil when browning it to keep things moist. Ground turkey is usually sold in 1-pound packages, so you’ll need to grab two for this recipe, and both fresh and frozen will work just fine as long as you thaw the frozen stuff completely before cooking.

Options for Substitutions

This keto casserole is pretty forgiving when it comes to swaps:

• Ground turkey: Ground beef, ground chicken, or ground pork all work great here. Just drain any excess fat if using higher-fat meats like beef or pork.
• Cheddar cheese: Mix it up with Monterey Jack, pepper jack for extra heat, or a Mexican cheese blend. You can also use mozzarella, though it’ll be milder in flavor.
• Bell pepper: Any color bell pepper works fine – red, yellow, orange, or green. You could also use poblano peppers for a slightly smoky taste.
• Taco seasoning: Make your own by mixing chili powder, cumin, paprika, garlic powder, and onion powder. This also lets you control the sodium content.
• Diced tomatoes: Swap with diced tomatoes with green chiles (like Rotel) for extra flavor, or use fresh diced tomatoes if you prefer. Just drain them well to avoid a watery casserole.
• Black olives: Green olives work just as well, or you can skip them entirely if olives aren’t your thing.
• Romaine: Any lettuce works for serving – iceberg, butter lettuce, or even shredded cabbage for extra crunch.

Watch Out for These Mistakes While Baking

The biggest mistake with this casserole is not letting the sautéed vegetables cool before adding the egg mixture, which can cause the eggs to scramble prematurely instead of forming a proper base layer – give them at least 5 minutes to cool down.

Another common error is skipping the simmering step for the turkey mixture, as this extra time allows the liquid to reduce and prevents a watery casserole that won’t hold together when you slice it.

Make sure your ground turkey is fully browned and broken into small pieces before adding the taco seasoning, since large clumps won’t absorb the flavors well and can create an uneven texture throughout the dish.

Finally, resist the urge to cut into the casserole right away – letting it rest for 10 minutes after baking helps everything set up properly and makes serving much cleaner.

What to Serve With Ground Turkey Taco Casserole?

This taco casserole is pretty filling on its own, but I love serving it with a big scoop of sour cream and some fresh guacamole on top. A simple side salad with romaine lettuce, cherry tomatoes, and a squeeze of lime juice keeps things light and adds a nice crunch to balance out the cheesy casserole. If you’re not strictly watching carbs, tortilla chips or warm corn tortillas on the side are perfect for scooping up extra bites. You can also set out some sliced jalapeños, extra black olives, and chopped cilantro so everyone can customize their plate however they like.

Storage Instructions

Store: This taco casserole is perfect for meal prep and keeps really well in the fridge. Just let it cool completely, then cover it tightly with foil or transfer portions to airtight containers. It’ll stay fresh for up to 4 days, making it great for easy weeknight dinners or packed lunches.

Freeze: You can definitely freeze this casserole for later! Cut it into individual portions and wrap each piece in plastic wrap, then place them in a freezer-safe container or bag. It’ll keep for up to 3 months, and you’ll have a quick keto meal ready whenever you need it.

Reheat: Warm up individual portions in the microwave for about 2-3 minutes, or reheat the whole casserole covered with foil in a 350°F oven for 20-25 minutes until heated through. Add fresh toppings like romaine, jalapeños, and cherry tomatoes after reheating for the best texture and flavor.

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 2400-2700
• Protein: 190-210 g
• Fat: 150-170 g
• Carbohydrates: 55-70 g

Ingredients

For the egg and vegetable layer:

• 1.5 tbsp oil (I use Chosen Foods avocado oil for high-heat cooking)
• 1 large onion (diced into 1/2-inch pieces)
• 1 bell pepper (seeded and diced into 1/2-inch pieces)
• 4 large eggs (room temperature, about 70°F)
• 1.25 tsp salt
• 0.75 tsp pepper

For the turkey filling:

• 2 lb ground turkey
• 1.5 tbsp oil
• 0.75 tsp garlic powder
• 0.25 cup taco seasoning (I prefer Siete brand for a clean keto option)
• 14.5 oz diced tomatoes (well-drained to prevent a watery casserole)
• 0.5 cup water

For the topping and garnish:

• 2.5 cups cheddar cheese (I like Kerrygold shredded sharp cheddar)
• 3 oz black olives (sliced into thin rounds)
• romaine (shredded into thin ribbons for crunch)
• jalapeno
• cherry tomatoes

Step 1: Prepare Mise en Place and Preheat Oven

• 1 large onion
• 1 bell pepper
• 3 oz black olives
• romaine
• jalapeno
• cherry tomatoes

Preheat your oven to 400°F and lightly grease a 9×13 inch baking dish or similar size with cooking spray or oil.

While the oven heats, dice the onion and bell pepper into 1/2-inch pieces, slice the black olives into thin rounds, and shred the romaine lettuce into thin ribbons.

Slice the jalapeno into rings and halve the cherry tomatoes.

This prep work ensures everything is ready when you need it, so the cooking process flows smoothly without interruption.

Step 2: Sauté Vegetables and Create the Egg Layer Base

• 1.5 tbsp oil
• 1 large onion
• 1 bell pepper
• 4 large eggs
• 1.25 tsp salt
• 0.75 tsp pepper

Heat 1.5 tablespoons of avocado oil in a large skillet over medium-high heat.

Add the diced onion and bell pepper, sautéing for about 8 minutes until they soften and develop light golden edges, which builds flavor through caramelization.

Transfer the softened vegetables to your prepared baking dish and spread them evenly across the bottom.

In a bowl, whisk together the 4 room-temperature eggs, 1.25 teaspoons salt, and 0.75 teaspoon pepper until well combined, then pour this mixture evenly over the vegetables in the dish.

The room-temperature eggs ensure even cooking throughout the casserole.

Step 3: Brown Turkey and Build the Taco Meat Layer

• 1.5 tbsp oil
• 2 lb ground turkey
• 0.75 tsp garlic powder
• 0.25 cup taco seasoning

While the vegetable and egg mixture sits, heat 1.5 tablespoons of avocado oil in the same skillet over medium-high heat.

Add the 2 pounds of ground turkey, breaking it apart with a spoon as it cooks, until it’s completely browned and no pink remains (about 5-7 minutes).

Sprinkle the 0.75 teaspoon garlic powder and 0.25 cup taco seasoning over the cooked turkey and stir well to coat evenly.

Cook for 1-2 minutes to bloom the spices and release their flavors.

I like to taste a small piece at this point to make sure the seasoning is balanced before moving forward.

Step 4: Simmer Turkey Mixture with Tomatoes

• 14.5 oz diced tomatoes
• 0.5 cup water

Add the 14.5 ounces of well-drained diced tomatoes and 0.5 cup water to the seasoned turkey, stirring to combine thoroughly.

Simmer this mixture over medium heat for 5-7 minutes, stirring occasionally, until it reduces slightly and the flavors meld together.

The draining of the tomatoes is crucial—it prevents excess moisture from making the casserole watery and mushy.

This concentrated taco meat will provide rich, flavorful layers in the final dish.

Step 5: Assemble Casserole and Bake

• taco meat mixture from Step 4
• 2.5 cups cheddar cheese
• 3 oz black olives

Carefully spread the hot seasoned turkey mixture from Step 4 in an even layer over the egg and vegetable base in the baking dish.

Top uniformly with the 2.5 cups of shredded sharp cheddar cheese, then scatter the sliced black olives across the surface.

Place the assembled casserole in the preheated 400°F oven and bake for 20 minutes until the cheese is melted and bubbly and the eggs are fully set.

Step 6: Rest and Serve with Fresh Toppings

• romaine
• jalapeno
• cherry tomatoes

Remove the casserole from the oven and let it rest for 3-5 minutes before serving.

This resting period allows the eggs to fully set and makes portioning cleaner.

Serve generous portions topped with the shredded romaine, fresh jalapeno slices, and cherry tomatoes for a fresh, crunchy contrast to the warm, cheesy casserole.

I find that these fresh toppings added at the end really brighten the rich flavors and give each bite nice textural variety.

Classic Low Carb Keto Ground Turkey Taco Casserole

Delicious Classic Low Carb Keto Ground Turkey Taco Casserole recipe with step-by-step instructions.

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 35 minutes mins

Total Time 52 minutes mins

Servings 6 servings

Calories 2550 kcal

Ingredients

  

For the egg and vegetable layer::

• 1.5 tbsp oil (I use Chosen Foods avocado oil for high-heat cooking)
• 1 large onion (diced into 1/2-inch pieces)
• 1 bell pepper (seeded and diced into 1/2-inch pieces)
• 4 large eggs (room temperature, about 70°F)
• 1.25 tsp salt
• 0.75 tsp pepper

For the turkey filling::

• 2 lb ground turkey
• 1.5 tbsp oil
• 0.75 tsp garlic powder
• 0.25 cup taco seasoning (I prefer Siete brand for a clean keto option)
• 14.5 oz diced tomatoes (well-drained to prevent a watery casserole)
• 0.5 cup water

For the topping and garnish::

• 2.5 cups cheddar cheese (I like Kerrygold shredded sharp cheddar)
• 3 oz black olives (sliced into thin rounds)
• romaine (shredded into thin ribbons for crunch)
• jalapeno
• cherry tomatoes

Instructions

 

• Preheat your oven to 400°F and lightly grease a 9x13 inch baking dish or similar size with cooking spray or oil. While the oven heats, dice the onion and bell pepper into 1/2-inch pieces, slice the black olives into thin rounds, and shred the romaine lettuce into thin ribbons. Slice the jalapeno into rings and halve the cherry tomatoes. This prep work ensures everything is ready when you need it, so the cooking process flows smoothly without interruption.
• Heat 1.5 tablespoons of avocado oil in a large skillet over medium-high heat. Add the diced onion and bell pepper, sautéing for about 8 minutes until they soften and develop light golden edges, which builds flavor through caramelization. Transfer the softened vegetables to your prepared baking dish and spread them evenly across the bottom. In a bowl, whisk together the 4 room-temperature eggs, 1.25 teaspoons salt, and 0.75 teaspoon pepper until well combined, then pour this mixture evenly over the vegetables in the dish. The room-temperature eggs ensure even cooking throughout the casserole.
• While the vegetable and egg mixture sits, heat 1.5 tablespoons of avocado oil in the same skillet over medium-high heat. Add the 2 pounds of ground turkey, breaking it apart with a spoon as it cooks, until it's completely browned and no pink remains (about 5-7 minutes). Sprinkle the 0.75 teaspoon garlic powder and 0.25 cup taco seasoning over the cooked turkey and stir well to coat evenly. Cook for 1-2 minutes to bloom the spices and release their flavors. I like to taste a small piece at this point to make sure the seasoning is balanced before moving forward.
• Add the 14.5 ounces of well-drained diced tomatoes and 0.5 cup water to the seasoned turkey, stirring to combine thoroughly. Simmer this mixture over medium heat for 5-7 minutes, stirring occasionally, until it reduces slightly and the flavors meld together. The draining of the tomatoes is crucial—it prevents excess moisture from making the casserole watery and mushy. This concentrated taco meat will provide rich, flavorful layers in the final dish.
• Carefully spread the hot seasoned turkey mixture from Step 4 in an even layer over the egg and vegetable base in the baking dish. Top uniformly with the 2.5 cups of shredded sharp cheddar cheese, then scatter the sliced black olives across the surface. Place the assembled casserole in the preheated 400°F oven and bake for 20 minutes until the cheese is melted and bubbly and the eggs are fully set.
• Remove the casserole from the oven and let it rest for 3-5 minutes before serving. This resting period allows the eggs to fully set and makes portioning cleaner. Serve generous portions topped with the shredded romaine, fresh jalapeno slices, and cherry tomatoes for a fresh, crunchy contrast to the warm, cheesy casserole. I find that these fresh toppings added at the end really brighten the rich flavors and give each bite nice textural variety.