This recipe ultimately comes from a book by Marcella Hazan. I think it's Marcella's Kitchen. (I totally recommend her cook books, she makes *wonderful* Italian recipes.)
At this point, my recipe doesn't much follow the one in the book. Which is why I won't just copy it over here. The good news is, regardless of how much detail I go into, this is an insanely forgiving recipe. It's tomatoes, garlic, and cream. You can make it *better*, but so long as you don't burn it, I don't think it can be *bad.*
Step one: Cut some garlic into slices. Personally, I use 1/2 to 3/4 of a head. Your mileage may vary. Throw them into a *big* (nonstick, if possible) skillet. Add a splash of olive oil. enough to keep the garlic loose in. Turn the heat on low, and just let the garlic sweat. The longer you can do this, the sweeter the garlic will be ultimately, but it's all about patience. If the heat is too high, it will brown. No big deal. when the garlic is soft, brown, or you're bored;
Step two: The tomato step. Again, it's a forgiving recipe. I think it calls for fresh plum tomatoes, but I hate slipping them, so I just used canned. The best is, of course, muir glen, but any of the canned varieties work. If possible, I recommend the brands that come in the finally diced. You want a 14-16 oz can. Diced, nothing but tomatoes (no spices, etc, until you've tried the basic and decide how you want to experiment. I have used Muir Glen fire roasted, and it's not the same, but not bad.) Dump the tomatoes in and put the heat on low again for about forever. I like to cook them down basically to nothing, ultra ultra soft. But I'm not all that fond of tomatoes. :) The original recipe said 'until the fat seperates' and if you watch it, there's a point when that happens and the oil starts gathering at the edges of the pan. like I said, though, it's not rocket science. When you're bored, and/or the tomatoes seems squishy enough:
Step three: Cream! I get the medium sized heavy cream container (for those who need realish numbers, this is the 2 cup container, and you're going to use about 2/3 a cup of cream at a time). Dump about a third in to the pan, stir throughly until it's a solid color (sort of pink-ish orange, depending on how much you cooked the tomatoes) Again, lowish heat, just let it cook waaaaay down. WAY. I accidentally thought I'd burned it the first time I did it this way, but no. It was awesome. Sweet/carmelized. Add another third, mix it completely as above, turn the heat up and hover over it until it's cooked down to a thicker sauce. It's an imperfect science, but you basically want it to at least be thick enough to cling to pasta. (So if you have the pasta done already, or are still testing it at this point, I advise taste testing with the pieces of pasta, to see how it stays on the pasta. If you cook it down too much, just add a little more cream.
And you're done. Pour it over a pound box of pasta, ideally cartwheels, otherwise radiators or rotini work well. You want lots of surface area to catch the sauce--nothing like penne or elbows or etc. They aren't *bad*, but they are less awesome. I have been making this dish for...10 plus years, and I still scramble to get the pasta and sauce done at the same time. I *think* if you start the pasta in the water after you add the cream the first time, it'll work out okay. Luckily, you can take a break with the sauce (turn the heat off after cooking down the first dose of cream.) while you try to get the pasta caught up. It will be *best* fresh, but works just fine reheated. (by 'best' I mean that 4 of us ate it tonight and there are no leftovers at all, and at least two of us had seconds. I have also eaten half of it myself in one sitting.)
There is also a step .5, which goes...somewhere. It is 'add salt.' I usually forget it while cooking. Also, taste it repeatedly. It is awesome, and every step only gets better. (by the cream steps, I usually try to talk myself around to just eating it out of the pan directly.)
And if you come visit, or I come visit you, I will make it for you, and you can stand at my shoulder and watch and taste and learn all my tricks.
ETA: I just remembered there's a non-vegetarian version of this as well which some may be interested in. If you make the sausage variation, it is worth finding the cartwheel pasta to go with it.
I will explain my method, you can reason out your own alternatives easy enough: Get yourself some sausage. About a pound I think, depending on your fondness for meat. If you actually live somewhere civilized enough to have a butcher (I miss Lewisburg for the butcher shop if nothing else.), it's the not-hot/Italian option. Just plain old sausage. If you have to make do with a grocery store, you want a bland sausage, ideally pork and little/nothing more. Breakfast sausage might be your best bet. Freeze it overnight or so, and then cut the sausage into rings a little wider than a pencil/basic pen. Wheels, basically. I don't like the sausage casing, which is one reason why I like freezing it--it peels off easily that way, but even with the skin, frozen is easier to cut into wheels. It cooks just fine from frozen or fresh, so that doesn't matter. You add the wheels to the pan while you sweat the garlic, so you only need enough oil to keep the sausage from sticking long enough to produce it's own fat. Sweat the garlic/brown the sausage (carefully, if you have removed the skin, so it holds together). When the garlic is done, move to step two, proceed normally. At the end, you'll have pasta cartwheels mixing with slices of sausage in much the same shape, for a nice blend of tastes and textures.