Directons
Toss shrimp with kosher salt and 3/4 teaspoon coarsely ground pepper.

Heat butter in a 12-inch heavy skillet over medium-high heat until foam subsides, then sauté shrimp, turning, until pink and just cooked through, 3 to 5 minutes. 

Reduce heat and add tequila, then increase heat to medium-high. Tilt skillet over gas burner to ignite tequila (or ignite with a long match; use caution, as flames may shoot up high). 

Cook, shaking skillet gently once or twice, until flames subside. Remove from heat and stir in crema. Serve sprinkled with scallion.