Grapefruit and Avacado Salad

Ingredients:
1/2 cup halved and very thinly sliced red onion
1 large lemon
1 tbs extra-virgin olive oil
1/2 tsp sea salt
1/4 tsp ground black pepper
3 small red grapefruit
1 large avocado
1/3 cup fresh pomegranate seeds
4 large fresh basil leaves
8 boston lettuce leaves
Place onion in a small bowl of cold water and soak. set aside.
Finely grate 1 tsp zest and squeeze 2 tbsp of lemon juice in bowl. Whisk zest of lemon, juice, oil, salt and pepper in a large bowl.
Peel grapefruit with sharp knife, removing all peel and white pith. Working over a medium bowl, cut segments from the surrounding membrains and let them drop into the bowl. Squeeze the peels and membrains over the bowl to extract the juice before discarding them. Halve, peel and pit avocado. Cut lengthwise into 1/4 inch slices, then cut the slices in half. Gently stir the avocado and pomegranate seeds into mixture.
Finely slice basil and drain the onion; gently stir into the grapefruit mixture. Arrange lettuce leaves on 4 plates, top with grapefruit mixture and serve immediately.