09/25/12 Edited to Add: I've made this a few times now without adding the heavy cream, because I forgot to buy it, and it's turned out just fine! I'm sure you could use any milk you want (2%, 1%, etc), but it won't be as delicious as with the whole milk.
Please don't let the thought of making your own cheese deter you from trying it! If you can bring liquid to a boil, you can make ricotta. This doesn't require any special equipment, aside from the cheesecloth, but I just used a clean tea towel. Also, I've gotta tell you, I do NOT like ricotta cheese. It's gritty and tastes like cardboard. I can handle it in lasagna because there's enough other stuff in there to distract from it. I tried a ricotta parfait once, and it didn't go well.
Anyway, this ricotta is not like that. It's creamy, and smooth and SO flavorful. I was literally eating pieces of it out of the colander. I cannot wait to try more recipes that feature this new wonderful cheese! I used this in the Zucchini Lasagna I mentioned yesterday, and it was divine. Be on the lookout for even more ways to use this new treat!
Homemade Ricotta Cheese from Framed Cooks
4 cups whole milk
One cup buttermilk
1/3 cup heavy cream
1. Line a fine mesh strainer with several folds of cheesecloth and set it in your sink.
2. Combine milk, buttermilk and cream in medium heavy saucepan over medium-high heat. Bring to a boil until cooking thermometer registers 185 degrees...if you don't have a thermometer, keep an eye on it to see when the curds (the solid white parts) are mostly separated from the whey (the cloudy liquid). This will take about 10 minutes...stir a couple of times during the boiling process.
3. Remove from heat and using a slotted spot, scoop spoonfuls of the curd into the cheesecloth-lined strainer, sprinkling with a little salt every few spoonfuls or so.
4. Let the ricotta drain for about 5 minutes and then taste to check the consistency. If you like it drier, then let it drain a little more. If you like it moister, stir in a tablespoon or two of milk. This ricotta is best used right away, but will keep for a day or two in the fridge.