I hope you enjoy the excerpt (and the mac and cheese!), which comes from the chapter on Tomato Sauce, Macaroni, and the Science of Pasta.
Baked ziti is the dish I make at the annual ski retreat that my friends and I take each year in New England. There are few pasta bakes that are easier to put together yet produce such ridiculously good results, particularly when it's snowing outside and you've got a whole cabinful of friends to feed.
Soak, Don't Boil
Here's something I've always wondered: when baking pasta, as in, say, lasagna or baked ziti, why do you always cook the pasta first? Aren't you inviting trouble by cooking it once, then proceeding to put it in a casserole and cooking it again? Well, there's the obvious first part of the answer to this question: pasta needs to absorb water as it cooks—a lot of water, around 80 percent of its own weight when perfectly al dente. So, add raw pasta directly to a baked pasta dish, and it will soften all right—it'll also suck up all of the moisture from the sauce, leaving it dry or broken.
Here's the thing: Dried pasta is made up of flour, water, and, on rare occasion, eggs. Essentially it's composed of starch and protein, and not much else. Starch molecules come aggregated into large granules that resemble little water balloons. As they get heated in a moist environment, they continue to absorb more and more water, swelling up and becoming soft.
Meanwhile, the proteins in the pasta begin to denature, adding structure to the noodles (something that is much more obvious when cooking soft fresh egg-based pastas). When the stars are aligned, you'll manage to pull the pasta from the water just when the proteins have lent enough structure to keep the noodles strong and pliant and the starches have barely softened to the perfect stage—soft but with a bite—known as al dente.
But who's to say that these two phases, water absorption and protein denaturing, have to occur at the same time? H. Alexander Talbot and Aki Kamozawa of the fantastic blog Ideas in Food asked themselves that very question, and what they found was this: You don't have to complete both processes simultaneously. In fact, if you leave uncooked pasta in lukewarm water for long enough, it'll absorb just as much as water as boiled pasta.
Here's what they had to say on the matter: "The drained [soaked] noodles held their shape, and since the starch had not been activated, they did not stick to one another and could be held without the addition of oil. Once we added the noodles to boiling salted water, we had perfectly cooked al dente pasta in just 60 seconds." Interesting indeed.
To try it out myself, I placed some macaroni in a bowl of warm tap water and allowed it to sit, pulling a piece out every 5 minutes to weigh how much water it had absorbed. After about 30 minutes, it had taken in just as much water as a piece of cooked boiled macaroni, all while remaining completely raw!
While the ability to cook presoaked pasta in just 60 seconds in itself is not all that exciting for a home cook (all it does is convert an 8-minute cooking process into a 30-minute soak plus 1 minute cooking process—hardly a time-saver), it's a very interesting application for restaurant cooks, who can have soaked pasta ready to be cooked in no time.
But what it does mean for a home cook is this: any time you are planning on baking pasta in a casserole, there is no need to precook it. All you have to do is soak it while you make your sauce, then combine the two and bake. Since the pasta's already hydrated, it won't rob your sauce of liquid, and the heat from the oven is more than enough to cook it while the casserole bakes. If you taste them side by side, you can't tell the difference between precooked pasta and simply soaked pasta. Think of what this means for lasagna! I know of at least six different common dental procedures that I'd rather have performed than to have to parcook lasagna noodles.
Keep the Sauce Simple
A basic red sauce is one of the five "mother sauces" of Italian cuisine that I identify in my book (the others being garlic and oil, ragú, cream, and pesto). It's an essential staple in any Western cook's pantry. Countless Italian-American restaurants are based on this sauce.
Marcella Hazan's recipe for tomato sauce may deliver the most culinary bang for your buck that you'll ever see. It's so simple it doesn't even need a full recipe—just simmer a 28-ounce can of whole tomatoes with 5 tablespoons unsalted butter and an onion split in half, crushing the tomatoes against the sides of the pot with a spoon—but the flavor you end up with is rich, fresh, and perfectly balanced. It's the butter that makes the difference. Unlike olive oil, butter contains natural emulsifiers that help keep the sauce nice and creamy. And the dairy sweetness works in tandem with the sweetness of the onions while rounding out the harsher acidic notes of the tomatoes.
Building from where Marcella leaves off, it's not a far jump to a classic Italian-American marinara sauce—tomato sauce flavored with garlic, oregano, and olive oil. Butter is still essential for smoothing out the rough edges of the acidic tomatoes, but here I like to substitute extra-virgin olive oil for half of it to bring some extra complexity into the mix. I make it in quadruple batches and store it in sealed Ball jars. Bottle while hot in sterile jars, seal them, and allow the sauce to cool to room temperature before refrigerating. It'll keep in the fridge for at least a month, ready to reheat and serve or incorporate into another recipe.
Now that we know how to make a basic marinara sauce and have learned how easy it is to soak, rather than boil, pasta for a baked casserole, it's just a short skip and a jump to classic baked ziti. The noodles get tossed with a pink mixture of tomato sauce, cream, and ricotta cheese, with a couple of eggs thrown in to lend structure to the casserole as it cooks. I also like to toss cubes of mozzarella cheese together with the pasta to form gooey, stretchy pockets. I top the whole thing with some more marinara, more cubes of mozzarella, and a grating of Parmesan.