Grilled Shrimp Tacos

1/2 cup sour cream 3 tablespoons mayonnaise 3 tablespoons milk 1/2 teaspoon ground cumin 1 1/2 lbs large shrimp , peeled 3 tablespoons butter , melted 2 large[...]

2 tablespoons olive oil 1 lime , zested and grated 1 teaspoon ground cumin 1 lb large shrimp , peeled and deveined salt , to taste ground black pepper , to[...]