5-oz. package fresh baby spinach
1 shallot, peeled and diced
1 tablespoon olive oil
4 ounces feta cheese, crumbled
salt & pepper to taste
1 sheet puff pastry, thawed
1 egg, beaten with 1 teaspoon water
Preheat the oven to 375 degrees F.
In a medium sauté pan, heat the oil and sauté the shallot until softened. Add spinach to a large frying pan with a tablespoon of water. Cook and stir until wilted, about a 2 minutes. Drain spinach well. Let cool a few minutes.
Mix spinach, cooked shallot, and feta together in a medium mixing bowl. Season with salt and pepper.
Roll out puff pastry sheet on a lightly-floured surface until it is about 20-30 % bigger. Cut sheet into about 3-inch squares (or close to that — choose your own size to use up the dough). Place about a tablespoon of mixture in the center of a dough square. Fold over to form a triangle. Press the edges together. Then seal by lightly pressing the tines of a fork along the edges. Repeat with the rest of the dough and the mixture. Place on a parchment-lined baking sheet. Brush lightly with beaten egg. With a paring knife, poke a small hole in the top of each one for steam.
Bake for about 20-25 minutes until golden. Serve hot, warm, or at room temperature.