Using the Serrated Utility Knife, peel the grapefruits to completely remove the white skin. Then using the Utility Knife, cut out the segments (pieces without white skin).

Peel the onion and chop it using the Herb Chopper. Zest the lemon or lime using the Speedy Grater, then juice it using the Cooks Maid. Add lime zest and juice and the olive oil to the shallots into the Herb Chopper and blend for a few seconds.

Cut the avocado in 2, remove the stone and scoop out the flesh from each halves using a tablespoon, try as much as possible to keep the flesh in 1 piece. Then slice it thinly using the Utility Knife and season with the contents of the Herb Chopper, some salt and pepper. Thinly chop the chives using the Utility Knife and add to the avocado. Keep a few sprigs for decorating at the end.

Build a tower by layering the grapefruit, then avocado and then again grapefruit and finish with avocado. Refrigerate until serving.

Just before serving, using the Chef Knife, thinly slice the gem lettuce, form a small nest in each serving plate and place the avocado and grapefruit tower in the middle of the nest. Decorate with some chopped chives.