Thaw the spinach and season with salt, pepper and garlic. Dice all ingredients.
Roll out the first puff pastry on a baking sheet. Spread on the puff pastry: Gouda cheese (about half), on top of the seasoned spinach, on top of very finely chopped onions, then the cooked ham, on top of the crumbled sheep`s cheese and finally the remaining Gouda cheese. Put the second puff pastry on top as a lid, press the edges well.
Put in the oven for about 25 minutes (see baking instructions on the puff pastry).