In a bowl, combine the eggs, sour cream and oil. In another bowl, combine the cornmeal, flour, baking powder and salt; fold in the chiles, green pepper, onion and pimientos. Add the egg mixture; mix well.
Pour half into greased 13x9-in. baking dish. Top with beef. Sprinkle with 1/2 cup cheddar cheese. Spoon remaining cornmeal mixture over top. Sprinkle with remaining cheese. Bake at 350° for 30 minutes or until a toothpick comes out clean.