1/2 cup Hellmann's® or Best Foods® Real Mayonnaise
Preheat oven to 375°. In shallow 8-inch baking dish, arrange blueberries; set aside.
In medium bowl, combine flour, brown sugar, oats and cinnamon. Stir in Hellmann's® or Best Foods® Real Mayonnaise. Using fingers, gently squeeze dough to form crumbs. Evenly sprinkle crumbs over blueberries.