Add the flour, sugar, and salt to a medium bowl and mix to combine.

Cube the cold butter and add it to the flour mix. Use your hands to toss in the flour, then use your fingers to smush the cubes of butter into the flour.

Repeat, working your way through the mixture, until all of the butter is roughly pea-sized or smaller, or well-smashed.

Add the sour cream and use a fork or spatula to mix, then switch to your hands to form it into a dough.

Spread out a piece of plastic wrap on the counter and transfer the dough on top. Form into an approximate square, about an inch thick. Wrap up and place in the fridge for 1 hour or up to 2 days.

Preheat the oven to 400°F.

Spray a 9x9-inch baking pan lightly with cooking spray.

Once the crust is almost done chilling, get the fruit ready. If desired, peel the peaches. Slice them, removing the pit, into roughly ½-inch slices or large dice and add to a large bowl (you should have about 5 cups).

Add the raspberries, sugar, cornstarch, vanilla (if using), and a pinch of salt. Mix to completely combine. Let sit for a few minutes while you roll out the crust.

Lightly flour a clean countertop and unwrap the crust. Use your hands to rub along the edges of the dough to help it warm up a bit.

Place on the floured counter and dust the top lightly with more flour.

Use a rolling pin to roll out the crust into a roughly 12x12 square. Roll from the center of the dough, smooshing together any cracks that form with your fingers as you go.

Rotate the dough periodically to make sure it doesn’t stick to the counter, and sprinkle on more flour as needed.

Toss the filling again and add it to the prepared pan. Spread out into an even layer.

Lay the crust over the pan. Gently lift the edges so that the crust is flush with the filling.

Fold the edges over a couple of times so that the crust has a clean edge all the way around that is flush with the pan.

Brush the top of the crust with a very thin layer of milk or cream and sprinkle generously with sugar, if using.

Use a sharp paring knife to cut about 6 vents in the top, each 1 to 2 inches long.

Bake until the filling is bubbly and the crust is golden brown and crisp, 40 to 48 minutes.

Depending on your oven, you may want to rotate the pan halfway through for even browning.

While the pandowdy is still hot, use the edge of a spoon to crack the crust in several places, allowing a little of the juicy filling to seep through.

Let cool for at least 30 minutes before serving. Pandowdy can be served warm or room temperature.