In a large pot, pour in the 3 liters of fresh whole milk. Heat the milk to 32°C (90°F). Stir gently to avoid scorching the milk on the bottom.
Once the milk reaches the desired temperature, sprinkle in the 1 teaspoon of citric acid and stir gently for about 30 seconds. This helps to acidify the milk, which is crucial for curd formation.
Dissolve the 30 drops of liquid rennet in 250 ml of cool, chlorine-free water. Slowly pour the rennet mixture into the warmed milk while stirring gently for about 30 seconds. Stop stirring and let the milk sit undisturbed for about 5-10 minutes. You'll see the milk start to set and form curds.
Once the curds have formed, cut them into 1-inch cubes using a long knife. Allow them to rest for another 5 minutes to firm up a bit.
Gently heat the curds to 41°C (105°F) while stirring gently. This process helps the curds expel whey and become firmer. Use a slotted spoon to stir occasionally for about 5 minutes.
Using a slotted spoon, carefully transfer the curds to a bowl lined with cheese cloth. Allow the curds to drain for about 5-10 minutes.
Sprinkle the fine sea salt over the curds and begin to knead the mixture. If the curds are too cool to stretch, you can microwave them for about 30 seconds to warm them up. The cheese should become smooth and elastic.
Once the cheese is stretchy, shape it into balls or logs. Place them in a bowl of cold water to cool and firm up.