Preheat your oven to 375°F (190°C) and lightly butter a 13” x 9” (33x22 cm) baking dish.
Evenly distribute the hash browns across the bottom of the prepared baking dish and set aside.
In a skillet over medium-high heat, crumble and cook the sausage until it browns thoroughly. Use a slotted spoon to transfer the sausage to the baking dish, layering it over the potatoes.
In the same skillet, sauté the diced onion and red bell pepper over medium heat, stirring frequently, until softened (about 5 minutes). If the skillet lacks grease, add 2 tablespoons of butter.
Stir in the minced garlic and cook for an additional 30 seconds, then layer the mixture over the sausage in the baking dish.
Sprinkle the shredded cheddar cheese evenly over the vegetables and sausage, mixing gently to combine all ingredients.
In a large mixing bowl, whisk the eggs until fully blended. Stir in the heavy cream, whole milk, Tabasco sauce, salt, pepper, and nutmeg. Mix thoroughly.
Pour the egg mixture evenly over the ingredients in the baking dish.
Place the casserole on the center rack of your preheated oven and bake for 40-45 minutes, or until the edges are firm and the center remains just slightly jiggly. Allow the casserole to cool for 10 minutes before serving.