1. Preheat oven to 400°F. Spray a 9-inch pie plate with nonstick cooking spray.

2. In a 10-inch skillet over medium heat, cook ground beef and onion until ground beef is brown and cooked through. Remove from heat and drain. Add in taco seasoning and stir to combine. Stir in green chilies and spoon seasoned beef into prepared pie plate.

3. In a medium bowl, combine milk, eggs and Bisquick mix, whisking until well combined. Pour into pie plate directly over beef.

4. Bake in preheated oven for 25 minutes or until knife inserted in center comes out clean. Sprinkle with cheese. Bake 8 to 10 minutes longer. Cool 5 minutes. If desired, serve with shredded lettuce, sour cream, tomatoes and salsa.