Separate puff pastry sheets and allow to thaw at room temperature. Cut out 2 spoons from each of the plates, preferably using a teaspoon as a template and cut generously. Fold the rest of the dough, do not knead, wrap in foil, chill and use the dough for other purposes.
Spread the spoons on two baking trays lined with baking paper. Place a small ball of aluminium foil under each spoon handle to create a typical spoon shape.
Whisk the egg, brush spoons with it. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) one after the other for 10-12 minutes. Remove, if necessary if the spoons open too much, press them together again and let them cool down.
Wash the tomatoes, dab dry. Heat oil in a pan. Fry the tomatoes for 1-2 minutes. Season with sea salt and remove from heat.
Drain the mozzarella, pluck it into pieces. Wash basil, dab dry and pluck leaves. Cover spoon with mozzarella, tomatoes and basil. Drizzle with pesto. Add the rest of the tomatoes.