Shell and devein shrimp. Rinse and cut into bite-size pieces. Chop cilantro.
Combine cilantro, lemon juice, cumin and cayenne pepper in a zip-lock bag to make marinade. Add shrimp pieces and set aside to marinate for 5 minutes.
Heat a skillet to medium heat and add shrimp with marinade. Stir-fry 1 to 2 minutes until shrimp turns orange. Remove skillet from heat and spoon shrimp out, leaving marinade.
Add sour cream to marinade in skillet and stir to mix.
Heat tortillas in a large skillet or microwave. Spread 2 teaspoons salsa onto each tortilla. Top with 1/2 shrimp mixture and sprinkle with 1 tablespoon cheese.
Spoon 1 tablespoon sour cream marinade mixture on top of shrimp. Fold tortilla in half, turn over in skillet to heat, then remove from pan. Repeat with second tortilla and remaining shrimp, cheese and marinade.
Cut each tortilla into 4 pieces. Garnish with cilantro and lemon wedge when ready to serve.