For puff pastry buns with cheese filling roll out puff pastry and place on a baking paper. Drain and chop the mozzarella, cut the dried tomatoes, bacon and bell pepper into small cubes, chop the spring onion into rings and finely chop the garlic cloves.
Mix everything and spread the mixture on the puff pastry. Season with salt, pepper, oregano and drizzle with a little olive oil.
Roll up the puff pastry with the filling and cut into 12 equal pieces. Put the baking paper on a baking tray, place the puff pastry snails on it, brush with egg yolk and bake in the preheated oven at 200 degrees for about 17 minutes.