Preheat your oven to 180 C. Grease a 8 inch spring form cake pan with butter or olive oil spray.
Brown ground beef and onion, drain, then add the taco seasoning and cook according to package direction.
To assemble, place 1 tortilla in the bottom of the cake pan, spread 1/3 of the refried beans on it, top with 1/3 of the meat and sprinkle on some cheese.
Add the 2nd tortilla, top that with 1/2 the rice, 1/2 the salsa, 1/2 the corn and cheese.
Add the 3rd tortilla, top that with 1/3 of the refried beans, 1/3 the meat, and sprinkle on some cheese.
Add the 4th tortilla, top with the remaining refried beans, then the meat, then the corn, then rice, then the salsa and top with the cheese.
Bake covered with foil for about 40 minutes, uncover and bake 10-15 minutes longer, let sit 5 minutes before cutting. After baking top with sour cream, diced onion, and shredded lettuce if desired.