Prepare the shrimp: In a medium bowl, toss the shrimp with olive oil, chili powder, cumin, salt, and pepper until coated.
Cook the shrimp: Heat a large skillet over medium-high heat. Add the seasoned shrimp in a single layer. Cook for 2 to 3 minutes per side until pink and cooked through. Remove from heat.
Make the lime crema: In a small bowl, whisk together the sour cream (or yogurt), lime juice, water, and salt until smooth. Add more water if you prefer a thinner consistency.
Warm the tortillas: Heat the tortillas according to package directions, either briefly in a dry skillet or wrapped in a damp paper towel in the microwave.
Assemble the tacos: Place a portion of cooked shrimp onto each warm tortilla. Top with shredded cabbage and a drizzle of the lime crema. Garnish with fresh cilantro and serve immediately with lime wedges.
Notes
For spicier shrimp, add 1/4 teaspoon of cayenne pepper to the seasoning mix.
If you prefer grilled shrimp, marinate the seasoned shrimp for 15 minutes before grilling over medium heat for 2-3 minutes per side.
Use Greek yogurt instead of sour cream for a slightly lighter crema.