Rub the garlic and the basil together with a bit of salt in a pestle or mortar or use a stick blender or kitchen aid. If you want, use more garlic, but I always find 1/4 enough.
Add the lightly roasted pineseeds and puree those too.
Put the mixture in a bowl and add half of the grated parmezan cheese to it. Stir carefully and then add as much oil so that everything binds together and forms a nice, smooth thick substance.
Add salt and pepper to taste and then the remaining cheese. Add a little more oil and try the taste. Keep adding cheese and oil untill you are satisfied with the thickness and the taste.
Lastly you can add a drop of lemonjuice but this is not really necessary.
Toast the slices of bread and rub them with a sliced piece of garlic. Spread a thick layer of pesto on the sandwich. Top with the slices of tomato and the mozzarella and finish with a drizzle of olive oil and some fresh basil leaves