Preheat the oven to 375°F.
In a skillet over medium heat, cook the ground beef until browned. Drain excess fat.
Stir in the taco seasoning and 1/4 cup of water. Cook for an additional 5 minutes until the mixture thickens.
Unroll the crescent roll dough and separate it into triangles.
Grease a muffin tin and press each triangle into the bottom and up the sides of the muffin cups to form a crust.
Spoon a tablespoon of the taco meat mixture into each crescent dough cup.
Top each with a tablespoon of salsa, followed by a sprinkle of shredded cheddar cheese.
Bake in the preheated oven for 12-15 minutes, or until the dough is golden brown and the cheese is melted.
Remove from the oven and let cool for a few minutes.
Top each cupcake with a dollop of sour cream, chopped green onions, cilantro, and jalapeño slices if desired.
