Ricotta is a "by-product cheese" (gross), made from the whey which is left over from other cheeses. "Ricotta" literally means "recooked." Leftover whey from hard cheeses is heated and combined with a little fresh milk. The result is a soft white curd cheese with a rather solid, kinda granular consistency. 20% fat.

Commercially-produced ricotta is made from cow's milk, but in rural areas sheep's or goat's milk is sometimes used.

The American Heart Association suggests using ricotta as a low-fat substitute for sour cream, but come on.