Preheat the oven to 375°F.
Lightly spray a muffin tin with cooking spray.
In a skillet over medium heat, cook the ground beef until browned, about 5-7 minutes. Drain excess fat and stir in the taco seasoning. Cook for an additional 2 minutes.
Roll out the biscuit dough and cut each biscuit into halves.
Press each half into the bottom and up the sides of the muffin tin cups to form a shell.
Spoon the seasoned beef into each biscuit shell, filling them about halfway.
Top with a tablespoon of salsa and a sprinkle of cheddar cheese.
Bake in the preheated oven for 12-15 minutes, or until the biscuit dough is golden brown and cooked through.
Remove from the oven and let cool for a few minutes.
Top each taco cupcake with a dollop of sour cream, diced tomatoes, black olives, and green onions before serving.