4 ounces rock shrimp (or peeled medium shrimp, deveined)
1 tablespoon minced shallot
2 teaspoons finely chopped peeled fresh ginger
1 tablespoon mayonnaise
2 teaspoon Sriracha (Asian chili sauce) or other chili sauce
1 teaspoon finely grated lime zest, plus 2 teaspoons fresh lime juice
1/2 medium baguette, sliced into 20 thin slices (less than 1/4 inch)
3 tablespoons unsalted butter, melted
Pulse shrimp, shallot, and ginger in a food processor until a coarse paste forms. Transfer to a bowl. Stir in mayonnaise, Sriracha, and lime zest and juice.
Heat broiler. Working in 2 batches, toast bread slices on a rimmed baking sheet 8 inches from heat source until golden brown, about 30 seconds. Remove from oven.
Flip bread, generously brush tops with butter, and spread with a thin layer of shrimp paste (about 1 teaspoon each).
Broil until shrimp mixture is opaque and cooked through and toasts are browned, about l minute. Serve warm.
If you decide to make this ahead of when you want to eat it, the shrimp paste can be refrigerated up to one day as well as the baguette slices in an air tight container at room temperature for one day.