For this quick snack we need:
- 1 sheet puff pastry, thawed at room temperature (about 40 min)
- 1 egg, lightly beaten with 1 tablespoon of water
- 1/2 cup grated Muenster cheese (or any other cheese you like)
- 1/4 cup grated Parmesan cheese
- 1 10-oz pack frozen spinach, thawed and well drained
- 1 spring onion, finely chopped
First heat the oven at 400F.
Mix the grated cheese with the chopped scallion

