Ingredients
2 tablespoons ketchup
1 tablespoon fresh lemon juice
1/2 teaspoon ground paprika
3/4 teaspoon chili powder, preferably ancho
Kosher salt and freshly ground pepper
2 tablespoons unsalted butter, plus more, melted, for brushing
2 cups frozen cooked salad shrimp (9 ounces), thawed, drained, and thoroughly patted dry (1 1/2 cups)
5 scallions, light-and dark-green parts only, thinly sliced (2/3 cup)
1 small avocado, halved, pitted, peeled, and cut into a 1/2-inch dice
4 slices sweet Hawaiian, potato, butter, or similar soft white sandwich bread
Butter-lettuce leaves, for serving
Preparation
In a bowl, stir together ketchup, lemon juice, paprika, chili powder, 1 teaspoon salt, and 1/4 teaspoon pepper. Melt butter in a small saucepan over medium-low heat. Add shrimp and cook, gently stirring, just until warmed through but not hot, 1 to 2 minutes. Transfer to bowl with ketchup mixture; stir to combine.
Gently fold in scallions and avocado; season to taste. Lightly brush one side of each bread slice with melted butter. Sandwich shrimp mixture and lettuce leaves between buttered sides of bread slices; serve immediately.
