Squeeze the lemon juice.

Place the milk in a saucepan and heat over moderate heat. Bring the milk to a boil—the edges should start to foam, and the center should bubble. Stir occasionally to prevent the milk from sticking to the bottom.

Remove the saucepan from the heat. Slowly pour the lemon juice into the milk in a thin stream, stirring constantly. Cover with 2 paper towels (or something else to retain moisture). Set the saucepan aside for 30 minutes to allow the curd to separate.

After the specified time, slowly pour through a mesh strainer or a regular strainer lined with gauze. If the milk has not curdled and separated, bring it to a boil again and add the same amount of lemon juice (repeat all steps). Set aside for about 5 minutes to allow the whey to drain completely. The cottage cheese may have a slight lemon flavor, so if you want to remove it, rinse the cottage cheese with water and set aside to drain again.

Once completely cooled and drained, transfer to a plate. Depending on the desired flavor, optionally add salt or sweetener and mix.