My thanks to crabplace.com for this recipe.
Crab Melt Sandwiches
1 lb. fresh lump crabmeat, cartilage removed
2 Tbsp. fresh lime juice, or to taste
1/2 cup mayonnaise
2 tsp. coarse-grained mustard
4 (1") thick slices Italian bread, with crust removed
4 tsp. fresh grated Parmesan cheese
unsalted butter, softened
Put crabmeat in a bowl and add 1 Tbsp. lime juice; toss to combine. In small bowl, whisk together remaining Tbsp. lime juice, mayonnaise, and mustard until smooth. Pour sauce over crab and toss to coat. Season crab mixture with salt and pepper and chill, covered, for 30 minutes.
Preheat broiler. Lightly toast bread. Lightly butter toast. Spoon 1/4 crab mixture into 1/2 cup measure. Holding toast on top of mixture in measure, invert crab onto the toast and set on an ugreased baking sheet. Repeat procedure with remaining crab mixture and toast and sprinkle 1 Tbsp. Parmesan over each sandwich. Broil sandwiches about 3" from heat until cheese is melted and golden, 1-2 minutes. Serves 4.