Avocado, Grapefruit and Tuna Salad

Ingredients

• 2 teaspoons finely chopped red onion
• 1 tablespoon fresh lemon juice
• Pinch of salt
• 2 tablespoons extra-virgin olive oil
• 1 pink or ruby-red grapefruit
• 1 firm-ripe avocado
• 1 (6-ounce) can solid white albacore tuna in water
• 1 oz baby arugula (2 cups)

Instructions

1. 1
   Stir together onions, lemon juice, and salt in a small bowl and let stand at room temperature 30 minutes. Add oil in a stream, whisking.
2. 2
   Peel grapefruit with a sharp knife. Cut segments free from membranes and transfer segments to paper towels to drain.
3. 3
   Halve avocado lengthwise. You''ll only need one half of this avocado, so rub a little lemon juice on the half that still has the seed in it, wrap tightly in plastic wrap and refrigerate. Use within a couple of days.
4. 4
   Halve remaining avocado half lengthwise and peel, then cut crosswise into thin slices.
5. 5
   Drain tuna and chunk with a fork.
6. 6
   Divide avocado and all of tuna between 2 salad plates and arrange grapefruit around them.
7. 7
   Top with arugula and drizzle with dressing. Serve immediately.