Preheat broiler. Spread mayonnaise on one side of each bread slice and arrange, spread side up, on a baking sheet. Broil 4 to 5 inches from the heat for 1 minute or just until starting to toast. Remove from oven; gently brush with soy sauce. Return to oven and broil 1 minute more.
Top bread slices with ham, cucumber, carrots, and cilantro. Add jalapeno slices and serve with lime wedges. Makes 12 servings.