Preheat your oven to 375°F (190°C) and line a muffin tin with cupcake liners.
In a skillet, cook the ground beef over medium heat until browned. Drain excess fat.
Stir in the taco seasoning and a splash of water; cook for an additional 5 minutes.
In a bowl, mix cornmeal, milk, and eggs until well combined.
Fold in the cooked beef, cheese, diced bell peppers, and tomatoes into the cornmeal mixture.
Spoon the mixture into the prepared muffin tins, filling each about two-thirds full.
Bake for 20-25 minutes or until the tops are golden and a toothpick comes out clean.
Allow the cupcakes to cool slightly before removing from the tin.
Top each cupcake with sour cream and garnish with jalapeños and cilantro.
Serve warm and enjoy your taco cupcakes!