For the salad, pre-cook the asparagus for 5 minutes and soak in ice water. Halve the avocado and asparagus and cut into small pieces, place in a bowl and season with lemon juice, rapeseed oil, salt and pepper. Pick up a pair of asparagus tips for decoration.
For the tartare, cut the salmon fillet into very small cubes and season with the finely chopped onion, olive oil, salt and pepper and season to taste. Chop the basil, save a few leaves for decoration and finally fold into the mixture.
Arrange the salad and the tartare on a plate and serve garnished with the asparagus tips and basil leaves.