Pour the milk into a tall pot over medium heat. Combine the lemon juice and water, stir it together, and add it to the milk. Heat the mixture to 97°F while stirring the pot.
Add the vegetable rennet drops to the water, mix well, pour into the heated milk mixture, cover with a lid, and let cook for 10 minutes.
Cut the cheese curd into large cubes and wait until the whey (liquid) settles.
Place a cheesecloth-lined colander in a bowl. Pull a cheese curd out of the pot with a skimmer, place it in the colander, and use the cheesecloth to squeeze the liquid out.
Heat water in a large pot to about 175°F and add the cheese ball. Knead the cheese with a spoon and remove it from the pot with a skimmer.
Cut the cheese ball in half. Take one half, stretch it out into a circle, place ricotta cheese in the middle, wrap the mozzarella ball up, and twist the end off to seal it. Place the mozzarella ball into an ice bath and let it chill until firm.
Roll out the pizza dough and coat it with tomato sauce. Cover the dough with mozzarella slices and bake at 400°F for about 10 minutes. Then pull the pizza out, place the stuffed mozzarella ball in the center of the pizza, and bake for another 10 minutes. Garnish the finished pizza with fresh basil for an authentic Italian flavor.
