01 - Preheat oven to 375°F. Line a baking tray with parchment paper.
02 - In a mixing bowl, combine the chopped artichoke hearts, spring onions, dill, parsley, Graviera cheese, Greek yogurt, 1 beaten egg, salt, and pepper. Mix until well incorporated.
03 - Lay one sheet of filo pastry on a clean work surface. Cover the remaining sheets with a damp towel to prevent drying out. Brush the sheet lightly with olive oil or melted butter. Place a second sheet on top and brush again, creating a stack of 2 layered sheets.
04 - Cut the layered filo into 4 equal strips lengthwise. Place 1 heaping tablespoon of filling near one end of each strip.
05 - Fold the corner of the strip over the filling to form a triangle. Continue folding in a triangular pattern along the length of the strip until the filling is fully enclosed.
06 - Repeat the layering, cutting, filling, and folding process with the remaining filo sheets and filling to yield approximately 16 puffs.
07 - Arrange all puffs on the prepared baking tray. Brush the tops evenly with the egg wash.
08 - Bake for 20 to 25 minutes until the puffs are golden brown and crisp.
09 - Allow to cool slightly and serve warm.