Wash and dry all produce. Slice the heirloom tomatoes into ΒΌ-inch thick slices or wedges, depending on their size and shape. For cherry-sized varieties, leave whole or halve them.
If using red onion, slice thinly and soak in ice water for 10 minutes to reduce sharpness. Drain and pat dry before using.
Arrange the mixed baby greens on a large serving platter or in a wide, shallow bowl.
Layer the sliced heirloom tomatoes on top of the greens, creating a colorful arrangement.
If using optional ingredients like red onion, mozzarella, or avocado, intersperse them among the tomatoes.
Drizzle the olive oil and balsamic vinegar evenly over the salad.
Scatter the torn basil leaves and any additional fresh herbs across the top.
Season with flaky sea salt and freshly cracked black pepper.
If using pine nuts or capers, sprinkle them over the top as a final garnish.
Allow the salad to rest for 5-10 minutes before serving to let the flavors meld together.
Serve at room temperature for the best flavor.
