Pink Grapefruit Avocado Salad

Adapted from Alice Waters

2 medium ruby grapefruits
1 small shallot, minced
1 teaspoon white wine or champagne vinegar
2 ripe Hass avocados, sliced 1/4 inch thick
Sea salt
2 tablespoons extra-virgin olive oil
Freshly ground pepper
Chopped fresh parsley

1. Using a sharp knife, cut the skin and all of the bitter white pith off of the grapefruits. Working over a bowl, cut in between the membranes to release the sections. Squeeze the juice from the membranes into the bowl.    
2. Add the shallot and vinegar to the bowl; let the dressing stand for 10 minutes.    
3. Season the avocado with salt and arrange on plates with the grapefruit sections.
4. Whisk the oil into the dressing; season with salt and pepper. Drizzle onto the grapefruit and avocado. Sprinkle with parsley and serve immediately.