In a nonstick, ovenproof 10 inch skillet over medium heat melt 2 T of unsalted butter. Add 2 cups of blueberries and 1/3 cup of sugar, stirring frequently until the mixture has the consistency of jam (10 to 20 minutes) Remove from heat. Add 2 more cups of blueberries, another 1/3 cup of sugar, 1 T all-purpose flour, 1 t lemon zest, 1 T lemon juice and 1/2 t nutmeg. Stir to combine. Make sure all the whole berries are evenly coated.[p]In a large mixing bowl, sift 1 1/4 cups all-purpose flour, 1/2 cup granulated sugar 1 1/2 t baking powder, 1/4 t kosher salt and 1/2 t cinnamon. In a separate bowl mix 1/2 cup of whole milk, 1 t vanilla extract, and 4 T of unsalted melted butter. Add this to the dry ingredients and mix until well combined scraping down the sides once.[p]Drop the batter in spoonfuls, starting in the middle and working out to the sides, leaving a 1 inch border of exposed fruit around the outside edge. The batter will expand while cooking so don't worry if there seems to be a shortage of batter.[p]Cook over indirect heat at 400 degrees until a skewer inserted in the center of the crust comes out clean (30 to 45 minutes)[p]Let stand 10 minutes and top with whipped cream if desired.
I like pouring half-n-half over mine in a bowl.