Spray a 9x13-inch casserole dish with nonstick cooking spray and set it aside.
In a large skillet over medium-high heat, brown the ground sausage with the taco seasoning. Drain the grease, remove the sausage, and sauté the peppers and onion until tender.
Return the sausage to the skillet and stir in the salsa and black beans. Remove the pan from the heat.
In a large bowl, whisk the eggs, salsa con queso, heavy cream, salt, pepper, and red pepper flakes until combined.
Arrange the tortillas in a single layer on the bottom of the prepared casserole dish.
Spread the sausage mixture over the tortillas, layer on 1 cup of the shredded cheese, then add the remaining sausage mixture.
Pour the egg mixture over the layers and top with the remaining cheese. Cover with foil and refrigerate for about 30 minutes.
Preheat the oven to 375°F. Bake the casserole uncovered for about 45 minutes, until the center is only slightly jiggly and the edges are bubbly and firm.
Serve warm with pico de gallo, avocado, cilantro, and sour cream.