In a saucepan, heat the milk until it is steaming and a light foam forms on the surface. Do not boil. 

Add the lemon juice. Remove from heat and stir for 1 to 2 minutes. The milk will begin to curdle. White curds will start to form and separate from the liquid (whey). If the milk does not curdle or only slightly, return it to the heat, stirring constantly until it separates. 

Line a sieve or strainer with 2 layers of cheesecloth, leaving it hanging over the edges. Place it over a large bowl so the sieve does not touch the bottom. 

Using a ladle, pour the curdled milk into the sieve. The whey will drain and only the curds (the base of the cheese) will remain in the sieve. If needed, empty the bowl if the sieve touches the liquid. Let drain for 10 minutes or until the liquid has finished dripping. 

Gather the cheesecloth around the cheese like a bundle. Holding it closed, rinse under cold running water to remove the excess taste of lemon or vinegar. 

Twist the top of the cheesecloth to gently squeeze out the cheese. The cheese should not come through the cloth. Place it in the sieve and shape into a thick disc. Place the sieve over the empty bowl, cover with a small plate, and place two 398 ml (14 oz) cans or the equivalent on top. Refrigerate for 4 hours. The longer the paneer sits in the refrigerator, the firmer it becomes. 

Remove the paneer from the cheesecloth. The cheese is ready to use or can be stored in an airtight container in the refrigerator for up to 2 weeks.