Dice the white onion into uniform 1/4-inch pieces and the green pepper into 1/2-inch pieces—uniform sizing ensures even cooking. Slice the mushrooms into 1/4-inch thick pieces. Heat a skillet over medium-high heat and sauté the onions first for about 2 minutes until they begin to soften, then add the green pepper and mushrooms. Cook for 4-5 minutes, stirring occasionally, until the vegetables are tender and any mushroom moisture has evaporated. This concentrates their flavor and prevents a watery bowl when heating later. Season lightly with salt and pepper, then set aside to cool slightly.

In a medium bowl, combine the cottage cheese with the dried oregano and a pinch of salt and pepper. Stir gently to distribute the oregano evenly throughout—I like to do this before assembling so the seasoning has time to infuse into the cottage cheese and distribute evenly, giving you better flavor in every bite. The cottage cheese will be your protein-rich base, so seasoning it properly is key.

Divide the tomato sauce evenly among your meal prep containers, creating a thin layer on the bottom of each. Layer the seasoned cottage cheese mixture from Step 2 on top of the sauce, then top with the cooked vegetables from Step 1. Distribute the pepperoni evenly over each bowl. Leave about 1/2 inch of space at the top of each container to allow for slight expansion during heating.

When ready to eat, heat the assembled bowl in a 350°F oven for 10-15 minutes until the cottage cheese is warmed through and slightly set at the edges, or use an air fryer at 400°F for 5-8 minutes for a faster option. The cottage cheese won't fully melt like traditional mozzarella, but it will warm and become slightly creamy. For a crispy pepperoni texture, I prefer the air fryer method as it crisps the edges nicely. Let cool for 1-2 minutes before eating.