Prepare the Filling: In a medium bowl, combine softened cream cheese, chopped crab meat, mayonnaise, cheddar cheese, Parmesan cheese, and green onions.
Add lemon juice, Worcestershire sauce, garlic powder, onion powder, and cayenne pepper (if using). Season with salt and pepper to taste.
Mix until well combined. Cover and refrigerate for at least 30 minutes.
Assemble the Puffs: Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.
Lightly flour a clean work surface. Unfold one sheet of thawed puff pastry and gently roll it out slightly.
Cut the puff pastry into equal-sized squares (about 2-inch). Repeat with the second sheet of puff pastry.
Remove the crab and cheese filling from the refrigerator.
Place a spoonful (about 1-2 teaspoons) of filling in the center of each square.
Fold one corner over to the opposite corner to form a triangle. Press edges firmly to seal, crimping with a fork if desired.
Place assembled puffs on the prepared baking sheet, leaving space between each.
Prepare Egg Wash and Bake: In a small bowl, whisk together the egg and milk (or water). Brush the tops of the puffs with the egg wash.
Sprinkle with everything bagel seasoning, sesame seeds, or chopped parsley (optional).
Bake for 15-20 minutes, or until golden brown and puffed up.
Remove from oven and let cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.
Serve: Serve warm or at room temperature.
Notes
For a more decadent treat, use real lump crab meat.
Experiment with different cheeses like Gruyere or Monterey Jack.
Add a pinch of Old Bay seasoning for a seafood flavor.
Finely diced red bell pepper or celery can be added to the filling.
Puffs can be assembled ahead of time and stored in the refrigerator until ready to bake. Add a few extra minutes to the baking time.
These puffs can also be frozen before baking. Place the assembled puffs on a baking sheet and freeze until solid. Then, transfer them to a freezer bag or container. When ready to bake, bake from frozen, adding a few extra minutes to the baking time.
Serve with ranch dressing, sweet chili sauce, or a creamy dill sauce.
Store any leftover puffs in an airtight container in the refrigerator for up to 3 days.
To reheat, bake them in a preheated oven at 350°F (175°C) for a few minutes until warmed through. You can also reheat them in a microwave, but they may not be as crispy.