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Breakfast Casserole

Breakfast Casserole
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This easy Breakfast Casserole bakes up golden and fluffy with eight whole eggs, melty mozzarella, sweet red onion, baby spinach, and bright red bell pepper. A hearty, protein-rich morning meal that feeds the whole family in under 40 minutes — naturally low-carb and endlessly customizable.

Ingredients

  • 8 large eggs
  • 2 egg whites (or 1 additional whole egg)
  • 1 tbsp olive oil, plus more for greasing the pan
  • 1 tsp minced garlic
  • ¾ tsp sea salt, or more to taste
  • Ground black pepper, to taste
  • 4.5 oz (125 g) mozzarella cheese, diced
  • 1 medium red onion, finely chopped
  • 1½ cups baby spinach, roughly chopped
  • 1 small red bell pepper, diced

Instructions

  1. Preheat your oven to 375°F (190°C) and lightly grease an 8×8 baking dish with olive oil.
  2. Heat 1 tbsp olive oil in a skillet over medium heat, then add the chopped red onion.
  3. Sauté the onion for 3 to 4 minutes until softened and just starting to turn translucent.
  4. Add the diced red bell pepper and cook for another 2 minutes until slightly tender.
  5. Stir in the minced garlic and cook for 30 seconds until fragrant — don’t let it brown.
  6. Add the baby spinach and toss until just wilted, about 1 minute. Remove from heat.
  7. In a large bowl, whisk the eggs and egg whites together with salt and pepper until fully combined.
  8. Spread the sautéed veggies evenly across the bottom of your prepared baking dish.
  9. Scatter the diced mozzarella over the veggies, tucking some pieces in throughout the layer.
  10. Pour the whisked eggs over the top, making sure the veggies and cheese are evenly covered.
  11. Bake for 22 to 28 minutes until the center is set and the top is lightly golden.
  12. Let it rest for 5 minutes before slicing — this helps the eggs firm up perfectly.

Notes

  • Whisk the eggs for a full 30 seconds until yolks and whites are fully blended for an even, soft texture.
  • Don’t skip the veggie sauté — it concentrates flavor and prevents a soggy casserole.
  • Test for doneness with a knife inserted in the center; it should come out clean.
  • Let the casserole rest 5 minutes before slicing for cleaner squares.
  • Substitute mozzarella with sharp cheddar or feta for a bolder flavor profile.
  • Refrigerate leftovers in an airtight container for up to 4 days, or freeze for up to 2 months.

Find it online: https://www.kitchenmomy.com/breakfast-casserole/