Clean lamb's lettuce, wash thoroughly and drain well. Clean the fennel (put the tender green aside), wash and cut lengthwise into thin slices. Beat 3 tablespoons of lemon juice, salt, pepper and oil and let the fennel soak through a little.
Roll up the salmon slices and cut them diagonally into small rolls about 1 1/2 cm thick. Wash and quarter the tomatoes and remove the seeds. Cut the tomatoes into small cubes. Cut avocados in half, remove stones.
Remove the fruit flesh, sprinkle with the remaining lemon juice and puree. Season to taste with salt and pepper. Drain the fennel a little and put it on a plate with the salmon rolls.
Turn the lamb's lettuce briefly in the marinade and serve with it. Pour the avocado cream into an extra bowl. Serve lettuce and cream garnished with tomato cubes and fennel green. Serve with crispy toast corners fried in butter.