In a large nonstick skillet, cook and crumble chorizo over medium-high heat until cooked through, 5-7 minutes. Drain on paper towels. In same skillet, cook and stir potatoes, onion and pepper until tender, 5-7 minutes. Add garlic; cook 1 minute longer. Remove from heat; stir in chorizo. Cool 15 minutes., Whisk eggs, cream, green chilies and chili powder. Layer a greased 11x7-in. baking dish with half each of the following: chorizo mixture, cheeses, and egg mixture; sprinkle with 1 tablespoon cilantro. Top with remaining chorizo and eggs; sprinkle with remaining cheeses and 1 tablespoon cilantro. Refrigerate, covered, overnight., Preheat oven to 350degrees. Remove casserole from refrigerator while oven heats. Bake, uncovered, until set and bubbling, about 35-40 minutes. Let stand 10 minutes before serving. Sprinkle with remaining cilantro. Serve with sour cream and pepper sauce.