Preheat oven to 375˚F (190˚C). Place tomatoes in single layer on parchment paper–lined baking sheet. Drizzle with 1 tbsp (15 mL) of the caesar vinaigrette; bake in centre of preheated oven for 15 min., or until skins start to split. Let stand in pan on rack for 5 minutes.
In a large bowl, combine roasted tomatoes (and any accumulated juices), lobster, mayonnaise, celery, red onion, chives, pickle, pepper, hot sauce and remaining caesar vinaigrette.
Divide lobster mixture evenly among lettuce leaves. Garnish with lemon wedges, and additional hot sauce, if desired.
To make 12 appetizer-size servings, substitute 24 cucumber slices or Belgian endive leaves for Boston lettuce leaves. Top each with 2 tbsp (30 mL) of the lobster mixture.