Spring's Coming Salad

Ingredients

• 1 small Vidalia onion, chopped
• 1/2 cup light olive oil
• 3 tablespoons balsamic vinegar, can substitute white balsamic vinegar
• 1 tablespoon plus 2 teaspoons granulated sugar
• 1 tablespoon mayonnaise
• 1/2 teaspoon Dijon mustard
• 1/4 teaspoon kosher salt
• 1 head bibb lettuce, washed and leaves roughly torn
• 1 (16-ounce) carton fresh strawberries, hulled, halved or quartered
• 1 avocado, diced
• 4 ounces blue cheese, optional, crumbled