Preheat your oven to 375°F. Generously grease a standard 12-cup muffin tin with butter or nonstick spray.

On a lightly floured surface, unroll the puff pastry sheets. Gently roll them out with a rolling pin to smooth any creases and create an even rectangle.

Spread the peach pie filling evenly over the pastry, leaving a 1/2-inch border around the edges. Sprinkle the sugar and cinnamon over the filling, if using.

Using a sharp knife or pizza cutter, slice the pastry into 2-inch-wide strips. Take each strip and roll it up into a loose spiral—don't make it too tight or the filling may squeeze out.

Give each spiral a slight twist and place it into a prepared muffin cup, spiral side up.

In a small bowl, whisk the egg with the water to make an egg wash. Brush this mixture over the tops of the cruffins.

Bake for 20 to 25 minutes, until the cruffins are puffed and golden brown. Let them cool in the pan for about 5 minutes, then transfer to a wire rack.

While the cruffins are still warm, whisk together the powdered sugar and milk until smooth. Drizzle the glaze over the tops and serve immediately.