01 - Preheat oven to 375°F. Line a baking sheet with parchment paper.
02 - Combine cooked chicken, cream cheese, cheddar cheese, mayonnaise, green onions, garlic powder, onion powder, salt, and black pepper in a mixing bowl. Mix until thoroughly blended.
03 - Roll out crescent roll dough or puff pastry and divide into 4 large squares or 8 triangles.
04 - Place a generous scoop of chicken mixture onto the center of each dough piece.
05 - Fold dough over filling to create pockets, pinching edges firmly to seal. For triangles, fold corners over; for squares, bring all corners together and pinch at the top.
06 - Arrange pockets on prepared baking sheet. Brush tops with beaten egg and sprinkle with sesame or poppy seeds if using.
07 - Bake for 20-25 minutes until golden brown and crisp.
08 - Let cool for 5 minutes before serving.