1 For the hamburgers: Soak the bread in a little lukewarm water. Peel and chop finely the shallots and sauté in 1 tablespoon of oil. Cool slightly. Combine ground meat, egg, shallots and bread. If mixture is too sticky add the breadcrumbs. Season with salt and pepper.
2 Form meat mixture into four patties. Heat the remaining oil in a pan and fry the patties for 5-6 minutes, turning occasionally.
3 Cut the rolls. Rinse the lettuce leaves and pat dry. Rinse the tomatoes, cut out stem and cut into slices. Place lettuce and tomato slices on bottom half of each of the rolls.
4 For the salsa: Rinse and cut the cucumber into small cubes. Rinse and cut the tomatoes into quarters, remove the seeds and dice. Peel the onion and chop. Mix the vegetables with the ketchup and season with lemon juice and Tabasco.
5 Spoon salsa on the bottom half of the roll and place hamburger on top. Spoon more salsa on top. Place other half of roll on top and serve.