Impossible Taco Pie

Heat oven to 400 degrees. Grease a 10 inch dish or pie plate. Cook and stir beef and onions over medium heat until beef is brown then drain of any grease. Stir in seasoning mix. Spread meat mixture into the pie plate, sprinkle with chillies. Beat milk, Bisquick, and eggs until smooth in a blender on high. Pour into pie plate on top of meat mixture. Bake 25 minutes. Then top with tomatoes and sprinkle with cheese. Bake until knife in center comes out clean about another 8 to 10 minutes. Cool 5 minutes. Serve with sour cream, chopped tomatoes, lettuce and olives if desired. Use your favorite taco sauce.