Preheat oven to 375 degrees. In a large bowl add the blueberries, sugar, cornstarch, lemon juice, lemon zest and vanilla extract. Toss the mixture to coat and set aside.
Lightly grease a 2 quart baking dish with non stick baking spray. Add the blueberry mixture to the baking dish.
In a separate medium size bowl, stir together the muffin mixes and milk just until blended. Pour muffin mix evenly over berries and spread the batter to the very edge.
Sprinkle a teaspoon of sugar over the top of the batter before baking. Bake cobbler for 30 – 35 minutes or until a toothpick inserted comes out clean and the cobbler is bubbly around the edges.
Cool and serve with a scoop of vanilla ice cream or a dollop of whipped cream.
Cook’s Note: If the top begins to brown too quickly cover with a piece of aluminum foil that has been spray with baking spray and continue baking.