• Pre-heat the oven to 400°F.
• Butter a 10-inch deep skillet and set it aside. Use a cast iron skillet if you plan to bake it on the grill.

Filling

• To a large bowl add the frozen peaches, blueberries, brown sugar, and cornstarch. Mix well ensuring the peaches are coated in the cornstarch and brown sugar, then set the bowl aside.

Shortbread Topping

• To a medium size bowl combine the sugar, cinnamon, flour, baking powder, and salt.
• Add the cold cubed butter pieces and combine with a fork, your fingers or a pastry cutter until well blended.
• Add the cold heavy whipping cream and stir until it's combined.

Assemble

• Stir the peach mixture again then add it to the buttered skillet.
• Drop tablespoons of the dough over the top of the peaches and blueberries, flattening them out as you place them over the peaches.
• Sprinkle the top of the dough with 1/2 tsp of granulated sugar.
• Bake for 30-35 minutes or until the peaches are bubbly and the topping is browned.

To Grill

• Pre-heat the grill to 400°F.
• Follow the above directions then instead of placing it into the oven place the cast iron skillet onto the grill grates.
• Close the lid to bake, checking periodically approximately 35-40 minutes. Try to maintain as close to the 400°F temp as you can.
• Bake until the skillet is bubbly and the top is browned. Be care when removing from the grill.
• If the top is still light in color you can put it under the broiler in your oven for a few minutes. MAKE SURE YOU KEEP AN EYE ON IT so it doesn't burn.