Summer Cornmeal Slump with Mango and Blueberry

Name: Summer Cornmeal Slump with Mango and Blueberry
Ingredients: 1 cup blueberries, washed and dried; 1 large fragrant, ripe but firm mango, cut into cubes (for a great tutorial on how to hedgehog your mango, head here: http://food52.com/blog...), yield should be about 1 ½ cups OR equal amount of strawberries, hulled and chopped; 2 teaspoons lemon zest, divided; 6 tablespoons unsalted butter, plus more for buttering your dish; 3/4 cup fine grind gluten free stone-ground cornmeal or corn flour – I used Bob’s Red Mill brand (do not substitute mesa, which is soaked in lime); 2 tablespoons medium grind gluten free stone-ground cornmeal; 1 1/2 teaspoons baking powder; 1/2 teaspoon kosher salt; 7 tablespoons sugar, divided; 1/2 cup well-shaken buttermilk; 2 large eggs; 3 tablespoons crème fraiche; 1 tablespoon maple syrup