Rinse the quinoa thoroughly under cold water until the water runs clear—this removes the bitter saponin coating and ensures a cleaner taste. Heat 1.5 tablespoons of olive oil in a medium pot over medium-high heat and add the rinsed quinoa. Toast for 2-3 minutes, stirring occasionally, until the quinoa becomes fragrant and starts to turn golden. This toasting step adds nutty flavor depth to the grain. Pour in 2.25 cups of vegetable broth and 0.5 teaspoon of salt, bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes. Remove from heat and let sit covered for 5 minutes to allow the quinoa to fully absorb the liquid, then fluff with a fork and set aside.

While the quinoa simmers, heat your oven to 350°F and lightly grease a 9x13 inch baking dish. In a large skillet over medium-high heat, cook 2 pounds of ground beef, breaking it apart with a spoon as it cooks, for 5-7 minutes until no longer pink. Drain off the excess fat by tilting the skillet and using a spoon to push the meat to the side. Add the thinly sliced mushrooms, diced onion, and minced garlic to the beef and sauté for 4-5 minutes until the vegetables soften and release their moisture—the mushrooms should begin to darken and the onions should become translucent.

Sprinkle 1.5 tablespoons of einkorn flour over the beef and vegetable mixture and stir constantly for 2 minutes—this flour acts as a thickening agent and helps create a rich, velvety sauce base. Pour in 1.25 cups of beef broth and bring to a boil, scraping up any browned bits from the bottom of the skillet to add extra flavor. Add 0.75 teaspoon of thyme, 1.25 teaspoons of paprika, 1.25 teaspoons of oregano, 1.25 teaspoons of salt, 0.75 teaspoon of pepper, and 0.25 teaspoon of cayenne pepper. I find that adding the spices all at once while the broth is hot helps them distribute evenly and bloom for better flavor. Simmer for 5 minutes to allow the flavors to meld.

Reduce heat to medium-low and slowly pour in 1.25 cups of room-temperature milk while stirring constantly—using milk at room temperature rather than cold helps prevent the sauce from curdling when combined with the other ingredients. Simmer gently for 5-6 minutes, stirring occasionally, until the sauce thickens slightly and coats the back of a spoon. Remove from heat and stir in 1.5 cups of freshly grated parmesan cheese until fully melted and incorporated. I recommend always grating parmesan fresh rather than using pre-shredded cheese, as it melts much more smoothly and creates a silkier sauce texture.

Fold the cooked quinoa from Step 1 into the beef and cheese sauce from Step 4 until evenly combined. Pour the mixture into the prepared 9x13 inch baking dish and spread into an even layer. Top with an additional handful of freshly grated parmesan cheese if desired for a golden, crispy top. Bake at 350°F for 20-25 minutes until the casserole is heated through and the top is lightly golden. The casserole is ready when you see gentle bubbles around the edges and the cheese on top turns light golden brown.

Remove the casserole from the oven and let it cool for 10 minutes before serving. This resting period allows the casserole to set slightly, making it easier to portion and serve without the filling falling apart. Garnish with fresh parsley for a pop of color and brightness.