For the dressing (makes 3/4 cup):
1 tbsp minced shallots
2 teaspoons Dijon mustard
2 tbsp white wine vinegar
6 tbsp 1% buttermilk
2 tbsp extra virgin olive oil
1/4 tsp garlic powder
1/2 teaspoon kosher salt
pinch black pepper

For the Salad:
1 head romaine, chopped (about 5 cups)
1 medium corn on the cobb, cooked and cut off husk*
4 to 5 large grape tomatoes, quartered
1/2 large avocado (3 oz), sliced
1/4 cup sliced red onion