Wash basil, shake dry, pluck leaves from the stems and cut into small pieces. Peel garlic and chop finely. Cut mozzarella into thin slices. Mix mozzarella, garlic, basil and olive oil, season with salt and pepper. Cover and chill for about 1 hour
Let the strudel dough sheets rest at room temperature for about 10 minutes. Wash, clean, quarter and seed the tomatoes. Cut the fruit flesh into small cubes. Drain the mackerels and pluck into pieces. Add the mackerel flesh to the mozzarella
Melt the butter. Remove 5 pastry sheets from the package. Immediately repack the rest well, store in the refrigerator and process in another way as soon as possible. Brush the dough sheets one after the other with butter and cut them into approx. 6 cm wide strips. Pour 1-2 tsp. of filling into each of the left-hand corners. Fold the left corner flush with the long side to form a triangle. Fold the triangle further flush to the end. Do the same with the remaining strips and filling
Heat the oil in a pan. Fry the filo pastry packs in it in portions all around for about 5 minutes. Serve hot or cold
Waiting time approx. 1 hour