Grill corn on preheated grill over medium heat. Remove from grill and let cool about 10 minutes. Cut corn kernels from the cob and set aside.
Make the dressing by stirring together buttermilk, canola mayonnaise, rice vinegar, chives, basil, garlic, and ground pepper. If dressing is too thick for your taste, add a little more buttermilk until you reach the consistency you desire.
Slice tomatoes and avocados. Stack tomato and avocado alternately. Sprinkle with corn and bacon.
Serve with 1 tablespoon dressing.
Cook time is for the bacon and grilled corn. If using pre-cooked bacon, cook time will be less.