1) Preheat oven to 350 degrees F. In a large skillet, add a drizzle of oil and sausage. Break up sausage and brown it well, cooking for 4-5 minutes over medium-high heat.
2) Add diced onion and pepper to the sausage and cook for another 1-2 minutes until veggies soften. Season with salt and pepper. Stir in green chiles and remove from heat.
3) Whisk eggs together with milk, paprika, and red chile flakes. Roughly chop tortilla strips and grate cheese.
4) In an 8×8 baking dish, spread out about a third of the tortilla strips. Then top with half of the sausage mixture and half the cheese. Pour in half of the egg mixture. Repeat: tortillas, sausage, cheese, eggs. Top the dish with the last 1/3 of the tortilla strips.
5) Bake the casserole at 350 degrees for 35 minutes or until the egg is set in the center of the dish. Remove and let cool slightly.
6) Serve casserole while hot with fresh chives.