STEP 2/3
Squeeze the juice out of the lemon and mix it with plain yogurt. Add whipped cream and milk and stir in salt, plain yogurt + lemon juice, when the top is covered. Bring to a boil while stirring evenly, and remove from the heat when there are soft particles.
STEP 3/3
Place a sieve in a suitable bowl and spread cotton cloth over it. Pour the boiled one gently into the cloth. You have to leave it like this for at least half a day to get the whey out. If you leave it for half a day or so, you'll get a solid lump of ricotta cheese like the picture above. You can put ricotta cheese separately in an airtight container and refrigerate it.