Baked Egg Muffin Cups Meal Prep: 12 Cups, 12g Protein Each, 5-Day Storage

Ingredients

• 10 large eggs
• 0.25 cup milk (whole milk preferred for richness)
• 1 cup shredded cheddar cheese
• 0.5 cup diced bell pepper (any color)
• 0.5 cup diced onion
• 4 oz cooked breakfast sausage or bacon, crumbled
• 0.5 cup baby spinach, roughly chopped
• 0.5 tsp kosher salt
• 0.25 tsp black pepper
• 0.25 tsp garlic powder
• 1 tbsp butter or oil spray (for greasing the tin)

Instructions

1. Preheat oven to 350°F (177°C). Grease a standard 12-cup muffin tin thoroughly with butter or oil spray — eggs are notorious for sticking to muffin tins, so don't skip this step or use only a light coating. Silicone muffin liners are an excellent alternative if you have them and make cleanup and removal significantly easier.
2. If using raw breakfast sausage, cook it fully in a skillet first, breaking it into small crumbles, then drain on paper towels. If using bacon, cook until crisp and crumble. Pre-cooking any meat fully is essential — the eggs bake for a relatively short time and won't fully cook raw meat in the center of the muffin cup.
3. In a large bowl or pitcher with a spout, whisk together the eggs and milk thoroughly until completely combined and slightly frothy — about 1 minute of whisking. Add salt, pepper, and garlic powder, whisk again. The milk helps create a slightly more tender texture and aids even cooking, but don't overdo it — too much liquid leads to watery muffin cups.
4. Distribute the diced bell pepper, onion, cooked meat, and chopped spinach evenly among the 12 muffin cups — aim for roughly 1 tablespoon of mixed filling per cup. Sprinkle shredded cheese evenly over the fillings, reserving about 2 tablespoons of cheese to add on top right before baking.
5. Pour the egg mixture evenly over the fillings in each cup, filling each about two-thirds to three-quarters full — eggs puff up while baking and will overflow if cups are filled past three-quarters. Use the pouring spout or a ladle for more control and less mess. Sprinkle the reserved cheese over the tops.
6. Bake for 18 to 22 minutes, until the eggs are puffed, set, and just barely golden at the edges. A toothpick inserted into the center should come out clean, or the centers should spring back lightly when touched. Watch closely after the 18-minute mark — eggs go from perfectly set to overcooked and rubbery within just a few extra minutes.
7. Remove from the oven and let cool in the tin for 5 minutes — this helps them release more easily and firms them up slightly so they hold their shape when removed. Run a thin knife or offset spatula around the edge of each cup if they're sticking, then gently lift each one out.
8. Transfer to a wire rack to finish cooling completely, about 10 to 15 minutes, before storing. This step matters — sealing them in a container while still warm traps steam, which makes the muffin cups soggy and shortens their storage life. Once fully cooled, store in an airtight container, ideally with a paper towel between layers to absorb any residual moisture, and refrigerate.