Preheat oven to 350°F Grease 12 muffin pan cups. Set aside.
Cook beef and onions in large nonstick skillet until meat is browned; drain. Remove from heat. Stir in olives, tomato sauce, 1/4 cup water, taco seasoning, hot sauce and egg; mix well.
Using a 4-inch round cookie cutter, cut each flour tortilla into 3 rounds. Fit tortilla rounds into prepared muffin cups. Fill each tortilla cup wih 1/4 cup meat mixture. Top each with sour ceam and cheese. Bake 25 minutes or until heated through.