Line a large colander with a large double layer of cheesecloth, and set it in your sink.
In a large wide pot, bring the milk to a gentle boil over medium heat, stirring frequently to avoid burning the bottom (a nonstick pot works really well for this purpose). This will take a little while so be patient!
Add the lemon juice and turn the heat down to low. Stirring gently, you should almost immediately see the curds (white milk solids) and whey (the greenish liquid) separate. Don't fret, this is perfect!
Remove the pot from the heat and carefully pour the contents into the cheesecloth-lined colander. Gently rinse with cool water to get rid of the lemon flavor. At this point, you could squeeze out some of the liquid, and serve with some honey and some nuts, almost like a fresh ricotta!
Grab the ends of the cheesecloth and twist the ball of cheese to squeeze out the excess whey. Tie the cheesecloth to your kitchen faucet and allow the cheese to drain for about 5 minutes.
Twisting the ball to compact the cheese into a block, place it on a plate with the twisted part of the cheesecloth on the side (this will ensure your block of cheese is nice and smooth!) and set another plate on top. Weigh the second plate down with cans of beans or a heavy pot. Move to the refrigerator and let it sit about 20 minutes.
Unwrap your beautiful disc of homemade cheese! You did it! You can now use this in any number of traditional Indian dishes, like saag paneer.
If the milk doesn't separate juice some more lemons and add another tablespoon or two. Boost the heat again and the milk should separate. Stir in a motion that gathers the curds together rather than breaks them up.