Preheat the oven by following the puff pastry package instructions.

Combine in a mixing bowl the thawed and drained spinach, chopped artichoke hearts, Parmesan, Gruyère, white cheddar, grated garlic, and cream cheese until everything is well blended and creamy.

Add lemon zest, crushed red pepper flakes, and kosher salt to taste into the mixture.

Roll out the puff pastry on a floured surface, aiming for a thin, even layer.

Scoop a spoonful of the spinach mixture onto the center of each piece of pastry.

Fold the pastry over the filling and seal the edges with a fork.

Brush the tops of your rolls with the whisked egg mixed with heavy cream for an egg wash.

Sprinkle everything bagel seasoning or sesame seeds on top if desired.

Bake in the preheated oven for the specified time on the puff pastry package.