Salsa, guacamole and/or sour cream for garnish, optional
Brown ground beef in a large skillet until cooked through; drain. Prepare taco meat according to taco seasoning mix directions. Set aside.
Combine 1 cup flour, undissolved yeast, sugar, baking soda and salt in a large bowl. Heat milk, water and butter to very warm (120° to 130°F). Pour into flour mixture; add eggs. Beat for 30 seconds with electric mixer to combine. Increase speed to high and beat for 3 minutes.
Stir in remaining 3/4 cup flour to make a stiff batter. Stir in cheese, bell pepper and green onion. Spoon half the batter into a greased 8 x 8-inch pan; top with taco meat. Dollop remaining batter over the taco meat. Cover with plastic wrap that has been sprayed with cooking spray and let rise in a warm, draft free place 40 minutes or until doubled.
Top with tortilla chips. Bake in preheated 375°F oven for 30 to 35 minutes or until golden brown. Serve hot and top with salsa, guacamole and/or sour cream, if desired.