Blueberry Cobbler - Cajun Sugar Pie

Ingredients

• 4 pints fresh blueberries
• ¼ cup granulated sugar
• ¼ cup brown sugar
• ¼ tsp ground cinnamon
• ⅛ tsp ground nutmeg
• 2 tsp cornstarch
• 1 cup unbleached all-purpose flour
• 1 tsp baking powder
• ½ tsp salt
• 6 tbsp unsalted butter, chilled and cut into small cubes
• ¼ cup boiling water
• cinnamon/sugar for sprinkling