1-First Step: Mise en place and oven prep Preheat the oven to 350 degrees and grease a 9×13-inch pan with cooking spray. Gather the ingredients: measure 2 pounds of sausage, crack 12 eggs into a large bowl, shred 2 cups of cheddar cheese, and slice the green onions. Having everything ready makes the assembly fast, which is helpful for busy mornings.

2-Second Step: Mix the egg base In a large bowl, combine the 12 eggs, 1 cup sour cream (light or regular), 1/4 cup milk, 2 cups shredded cheddar cheese, 1 teaspoon salt, and 1/2 teaspoon ground black pepper. Mix lightly until the mixture is homogeneous but not overbeaten. Hand-whisking for 1 to 2 minutes gives a light texture without extra tools. If you prefer a slightly firmer custard, reduce the milk by a tablespoon.

3-Third Step: Cook the sausage Heat a skillet over medium heat and cook the 2 pounds sausage, breaking it into small pieces until browned. This typically takes 6 to 10 minutes depending on the sausage type. Drain the grease well on paper towels to avoid a greasy casserole, then add the cooked sausage to the egg mixture. If you swap in lean turkey sausage or ham, cook until just browned to maintain moisture.

4-Fourth Step: Sauté the vegetables In the same skillet (use the leftover fond for flavor), sauté the diced 1/2 green bell pepper, 1/2 red bell pepper, and sliced 4 green onions for 2-3 minutes over medium heat. You want them softened but still bright. Add them to the egg and sausage mixture and stir everything together so flavors distribute evenly. For a softer vegetable texture, cook for an extra minute or two; for a crisper bite, add them raw to the mixture.

5-Fifth Step: Assemble and bake Pour the combined mixture into the prepared 9×13-inch pan. Spread evenly and tap the pan gently on the counter to release large air bubbles. Bake in the preheated oven for 35-50 minutes until the edges are set and the center has a slight jiggle. Start checking at 35 minutes; total bake time depends on oven accuracy and how full the pan is. The casserole will firm up as it cools, so a touch of jiggle at the center is normal.

6-Final Step: Resting, serving, and storage notes Remove the pan from the oven and let it rest for 10 to 15 minutes before slicing. Resting helps the custard set fully and makes the casserole easier to portion. Serve warm with a side of fruit or light greens. Leftovers keep well in the refrigerator for 3-4 days and reheat nicely in the microwave for 30 to 60 seconds per portion.