How to Make It
In a large bowl, whisk the lemon juice with 1/4 cup of the olive oil. Season with salt and pepper. Halve and pit the avocados, and cut them into 1/4-inch dice. Add to the bowl and toss with the dressing. Fold in the tomatoes and cilantro. Refrigerate the salad until chilled.
Light a grill or preheat a grill pan. Thread each shrimp lengthwise onto a skewer to keep it straight. Brush the shrimp skewers with olive oil and season them with salt and pepper. Grill the shrimp over moderately high heat until cooked, about 2 minutes per side.
Spoon the avocado salad onto 10 salad plates. Top each salad with a warm grilled shrimp and serve at once.