Fresh ricotta is made using whey left over from making fresh mozzarella, I am going to show you how to make a similar cheese using milk and cream. I prefer freshly made curd cheese in my dishes rather than store-bought, because the flavor profile has more depth.
Pour the milk and cream into a wide, heavy-bottomed nonreactive saucepan and bring to a simmer over high heat. Turn off the heat, add the lemon juice and salt, and allow to cool without stirring for 5–10 minutes: you will see curds forming.
Line a strainer or colander with a single layer of cheesecloth and place it in the sink. Gently scoop the curds out of the saucepan into the lined colander. (Don't simply pour everything at once, as you don't want to break up the curds that have formed.) Once you have scooped all of the curds into the colander, let the ricotta drain until it is no longer runny, but a thick, spoonable consistency, 15–20 minutes.
The warm ricotta can be served right away. If you are serving it later, or need it to be drier (e.g., for ravioli filling or cheesecake), lay a wooden spoon across the colander. Lift the corners of the cheesecloth and tie them around the spoon, creating a bundle. Place the wooden spoon over a bowl so the ricotta bundle hangs suspended over the bowl, allowing additional liquid to drain away. Place the draining ricotta in the refrigerator overnight, or until it reaches desired consistency.
This ricotta goes well with Chef Silverton's fett'unta.