Place ground beef in a deep skillet.
Cook over medium high heat until evenly brown.
Drain, then season with taco seasoning and add water. Simmer for 10 minutes.
Add salsa, refried beans and corn; heat through.
Place about 1/3 cup of meat mixture in the bottom of a round baking dish...quiche pan, cast iron skillet, or round casserole dish.
Place 1 tortilla at bottom of dish.
Add a layer of meat mixture (about 2/3 cup); sprinkle with a layer of cheese.
Continue alternating tortilla, meat mixture and cheese...ending with a thin layer of meat mixture.
Cover and bake at 350°F for 30 minutes.
Top with a layer of cheese.
Bake uncovered for an additional 10 minutes or until cheese is melted.
Let stand several minutes before serving.
Garnish with olives, guacamole, tomatoes, shredded lettuce and sour cream...as desired.