How to Make It
Bring a large saucepan of water to a boil and prepare an ice water bath in a large bowl.
Using a small paring knife, make a shallow X in the bottom of each tomato. Plunge the tomatoes into the boiling water for 10 seconds. Using a slotted spoon, transfer the tomatoes to the ice water bath. Peel, core and seed the tomatoes; save the ice water bath.
In a blender, puree the tomatoes with 1/4 cup of the olive oil and the vinegar until smooth. Transfer to a bowl and season with salt and pepper. Set the bowl in the ice water bath to chill the soup.
In a medium bowl, combine the crabmeat with the onion, basil, jalapeño and lime juice. Gently fold in the chopped avocado and season with salt and pepper. Ladle the tomato soup into shallow bowls and drizzle with the remaining 4 teaspoons of olive oil. Mound the crab guacamole in the center of each bowl of soup and serve.