1/2 cup extra-virgin olive oil, plus more for grilling
1 tablespoon finely minced garlic
Freshly ground black pepper
1/4 cup minced Italian parsley leaves
Slice the red onion and put it in a bowl with the lemon juice. Dice the avocado, add it to the bowl, and toss well to coat. Add the olive oil and garlic and season with salt and pepper. Just before serving stir in the parsley.