Heat oven to 400 F.

Spray muffin tin with nonstick cooking spray.

Sprinkle flour on work surface. Flatten pastry sheet and roll into rectangle.

Drizzle caramel sauce over pastry and spread within 1/2 inch of edges.

Sprinkle chopped walnuts over caramel sauce.

Starting on short end, evenly roll pastry with filling to other end.

Cut pastry into nine pieces. Place pastries cut side up into muffin cups.

Bake 22 minutes, or until golden brown. Immediately remove from pan to wire rack. Let cool 10 minutes. Drizzle with additional caramel sauce and dust with powdered sugar.