Cook the gnocchi in salted water according to the instructions on the packet. Then mix the warm gnocchi with 3 tablespoons of olive oil.
Cut the tomatoes into pieces, drain the tuna and pull apart. Cut the mozzarella into small cubes and quarter the olives, coarsely chop the basil leaves.
Now add all the ingredients and the remaining olive oil to the gnocchi and mix everything carefully. Use the 2 tablespoons of balsamic vinegar, black pepper from the mill and garlic salt to taste.