Add the onion, garlic, cilantro, jalapeño, and corn and toss to mix.
Place the mayonnaise, lime juice, salt, and black pepper in a small bowl and whisk well to combine.
Pour the dressing over the shrimp mixture and carefully toss to coat the salad evenly.
Evenly divide the shrimp salad between two sandwich buns on top of lettuce leaves.
Serve immediately. Alternatively, you can refrigerate the shrimp salad for 2-3 days until ready to serve and assemble the sandwiches right before serving.