Preheat your oven to 350°F and butter a 9x13-inch baking dish generously. Cube your bread and scatter it across the bottom of the dish, then arrange turkey strips on top.
Sauté diced onions and bell peppers in a skillet over medium heat with 1 tablespoon butter for 5-7 minutes until softened. Stir in fresh spinach and cook until wilted, about 2 minutes more.
Spread the sautéed vegetables evenly over the bread layer, then sprinkle diced tomatoes and shredded cheese across the top. This creates distinct flavor pockets throughout your dish.
Whisk together eggs, milk, salt, pepper, garlic powder, and paprika in a large bowl until completely combined. Pour this mixture slowly over the bread and vegetable layers, pressing down gently with a spatula.
Let the cozy egg breakfast recipe sit for 10 minutes before baking—this allows the bread to absorb the egg custard fully. Transfer to the preheated oven.
Bake for 40-45 minutes until the center is set but slightly jiggly, and the top is golden brown. A knife inserted in the center should come out clean with no raw egg remaining.
Remove from oven and let rest for 5 minutes before serving. This allows the proteins to set completely and makes portioning easier.