Slice heirloom tomatoes with a sharp serrated knife. Set the slices on a paper towel to soak up extra water. 

Meanwhile, julienne the basil and set aside. 

Next, cut the avocado in half. Remove and discard the pit. Slice the avocado into thin slices. 

Divide the tomato slices between six small plates. Top each of the plated tomatoes with a few avocado slices. 

Finally, sprinkle each plate with a pinch of salt and pepper, and some julienne basil. 

Serve with a side of balsamic vinegar on the table. Alternatively, you could top each plate with a small drizzle of balsamic. 

Serve immediately and enjoy!