1. Combine first 3 ingredients in a medium bowl.
2. Combine mayonnaise and next 6 ingredients (through red pepper) in a small bowl, stirring with a whisk. Gradually add oil, stirring well with a whisk. Drizzle dressing over crab mixture, tossing well to combine. Spoon about 1 1/2 tablespoons crab mixture in center of each lettuce leaf.