Preheat oven to 180c/350f.
If your potatoes (4) have dirt on the outside (mine did) wash and scrub them well, then dry with paper towel.
Pierce each potato quite a few times with a fork, then wrap each one in a piece of aluminium foil. Place potatoes on a baking tray and bake for an hour or until tender. You can test to see if the potatoes are cooked by piercing the potato through the foil with a toothpick.
Meanwhile, combine butter (80g/4 tbsp) and garlic (1 clove, minced) then set aside.
In a small fry pan, fry chopped bacon (2 rashers) until cooked then also set aside.
Open the foil and allow potatoes to cool slightly (see my notes), then make a slice through the centre of each potato, about half way through. Insert a fork into the slit and fluff up the soft potato flesh inside - doing your best to keep the skin intact.
Place 1 tablespoon of garlic butter and a small amount of mozzarella cheese (100g/1 cup in total) plus salt and pepper (to taste) into the slit of each potato and mix them together with the fluffy potato flesh.
Then add remaining cheese and mix until the centre of the potato is creamy and smooth. Then top away!