Preheat oven to 350°F and grease a 9x13-inch baking dish.

In a large skillet over medium heat, cook the breakfast sausage and diced onion with chili powder and cumin until the meat is browned. Set aside.

In a large bowl, whisk together eggs, milk, salsa verde, salt, black pepper, and garlic powder.

Add cubed cornbread, 1 1/2 cups of the shredded cheese, diced red and green peppers, and the cooked sausage mixture to the bowl. Gently stir to combine.

Transfer the mixture to the prepared baking dish and sprinkle the remaining 1/2 cup cheese on top.

Bake for 25–30 minutes, or until the top is golden and the casserole is set. Let rest slightly before serving.