1-First Step: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish to prevent sticking.

2-Second Step: In a large bowl, whisk together 6 large eggs, 3 cups of milk, ½ teaspoon dry mustard powder, ½ teaspoon salt, and ½ teaspoon black pepper until fully combined.

3-Third Step: Layer half of the 12 slices of thick sliced bread cubed (about 14 cups) evenly in the greased baking dish. Sprinkle half of the 12 slices of cooked and crumbled bacon or 1 cup diced ham, 3 thinly sliced green onions, ½ finely diced red bell pepper, and 4 cups shredded cheddar cheese (or Monterey Jack or a cheese blend) over the bread.

4-Fourth Step: Repeat the layering with the remaining bread, bacon or ham, green onions, red pepper, and cheese to build a hearty strata.

5-Fifth Step: Pour the whisked egg mixture evenly over the layers to moisten all the bread, then cover the dish tightly with foil and refrigerate for at least 3 hours or overnight.

6-Final Step: In the morning, let the casserole sit at room temperature while preheating the oven to 350°F. Bake covered with foil for 45 to 55 minutes until set (up to 80 minutes for double pans). For a golden, crispy top, broil for 3 minutes after baking. Allow it to cool slightly before serving, and adjust for preferences as needed.