Step 1

Brush 2 teaspoons lemon juice over flesh of avocados; set aside.

Step 2

Add lemon juice, salt, and tarragon to the reserved grapefruit juice; season with pepper.

Step 3

Whisk in olive oil in a slow, steady stream. Add grapefruit sections and toss gently.

Step 4

Place each avocado half on a plate. Top with grapefruit mixture, dividing evenly.

Step 5

Serve immediately.