In an 8-inch sauté pan, melt 1 tablespoon of the butter or oil over medium heat. When it is heated, but not brown, add the garlic and shrimp, and cook, stirring, until the shrimp are pink. Stir in the chipotles and salt and remove from the heat.
Preheat a heavy pan or griddle over medium heat and brush it lightly with some of the remaining butter or olive oil. Set a corn tortilla on the griddle and scatter 2 tablespoons of shredded jack cheese evenly over the tortilla.
Set 3 or 4 shrimp on one side of the tortilla. When the cheese starts to melt, fold the tortilla in half over the shrimp, and continue to cook on both sides until the cheese is melted and the tortilla is lightly crisped and golden brown.
Open the taco. Dollop 1 teaspoon of chipotle salsa on top of the shrimp and follow with a tablespoon each of guacamole and mango salsa.
Tuck a couple of cilantro sprigs into the opening and serve right away.