Preheat your oven to 350°F and line a standard 12-cup muffin tin with cupcake liners. Drain the canned peaches thoroughly and cut them into 1/2-inch pieces, then toss them with the 1/2 teaspoon cinnamon and 2 teaspoons sugar in a small bowl. This quick maceration helps the peaches release their juices and flavor the cupcakes from the inside.
In a large mixing bowl, whisk together the flour, 1 cup sugar, baking powder, 1 1/2 teaspoons cinnamon, and salt. Create a well in the center and pour in the melted butter, egg white, whole egg, vanilla extract, and milk. Stir until just combined into a smooth batter—don't overmix, as this keeps the cupcakes tender. I like to use both an egg white and a whole egg here because the white adds lift while the yolk contributes richness and moisture.
Place 3 pieces of the cinnamon-sugar peaches from Step 1 into the bottom of each lined cupcake cup. Divide the batter from Step 2 among the liners, filling each about 3/4 full. Top each with 3 more peach pieces, nestling them gently into the batter. Bake for 19-21 minutes, until a toothpick inserted into the cake portion (not through a peach) comes out clean or with just a few moist crumbs. The peaches will create pockets of fruity goodness throughout.
Remove the cupcakes from the oven and let them cool in the pan for 5 minutes, then turn them out onto a wire rack to cool completely. This prevents them from steaming and becoming soggy on the bottom.
In a chilled mixing bowl, beat the heavy cream until soft peaks form. Add the powdered sugar, cornstarch, and 1 1/2 teaspoons vanilla extract, then continue beating until stiff peaks form. The cornstarch acts as a stabilizer, helping the whipped cream hold its shape longer—I find this especially useful if the cupcakes will sit out for a bit before serving.
Once the cupcakes from Step 4 are completely cooled, generously top each one with a dollop of the whipped cream frosting from Step 5. Dust the top of each cupcake lightly with additional cinnamon for a classic cobbler finish. Serve immediately or refrigerate until ready to serve.