Preheat oven to 400°F. Line a work surface with a little flour to prevent sticking.
Roll out 1 puff pastry sheet on the floured surface to about 15 × 12 inches.
Spread 1/2 cup pesto evenly over the rolled pastry.
Sprinkle 1/2 cup grated Parmesan evenly over the pesto.
Using a sharp knife or pizza cutter, cut the pastry into 1-inch-wide strips along the long side (you should get ~15-inch-long strips).
Fold each strip in half (bringing the ends together), pick it up, twist it a few times, and place the twist on an ungreased baking sheet about 1 inch apart, seam side down.
Repeat steps 2–6 with the second puff pastry sheet, using the remaining 1/2 cup pesto and 1/2 cup Parmesan.
Brush each twist with the beaten egg.
Bake for about 15 minutes, or until the twists are puffed and golden brown.
Transfer twists to a wire rack and cool for about 5 minutes before serving.
Notes
I used pesto from a jar. You’re free to use your own homemade pesto.
Other sauces such as marinara or red pesto will work for this recipe as well.