Drain the tuna. Peel the avocado and cut into small cubes. Wash, clean and finely dice the celery. Pluck or cut the tuna into small pieces. Wash the lettuce leaves and dab dry.
Mix syrup, vinegar and oil, season with salt and pepper. Wash the chives, dab dry and cut into small rolls. Stir into the vinaigrette. Put the lettuce leaves on a plate. Mix tuna, avocado and celery and arrange on top.
Add a little vinaigrette. Add slices of baguette.