How to Make It
Stir together vinegar, sugar, and crushed red pepper in a medium microwave-safe bowl. Microwave at HIGH until hot and sugar has melted, 1 to 2 minutes. Add shallots. Let stand 5 minutes; drain.
Preheat grill to medium-high (about 450°F).
Using a sharp knife, cut lobster tails in half lengthwise; coat flesh with cooking spray. Place lobster tails, flesh side down, on grill grates; grill, uncovered, until grill marks appear, about 4 minutes. Turn lobster tails over, and grill, uncovered, until flesh is opaque, about 2 minutes. Remove from grill, and cool 10 minutes.
Meanwhile, lightly coat bread with cooking spray. Cut each bread piece in half. Place bread, cut side down, on grill grate; grill, uncovered, until toasted, about 1 to 2 minutes.
Remove meat from lobster tails, and chop. Discard shells. Stir together lobster meat, oil, tomato, lemon juice, parsley, basil, salt, and black pepper in a medium bowl.
Spread 1 1/2 tablespoons mayonnaise on cut side of each bread piece; top evenly with lobster mixture and pickled shallot. Cut each bread piece into 5 slices.