At flour + water, central kitchen and salumeria in San Francisco, Chef Thomas McNaughton is famous for his pasta dishes. After learning to make fresh pasta by hand in Bologna, he brought his skills to his restaurants, using traditional Italian techniques and California ingredients to create his own unique spin.
We partnered with Thomas this month upon the release of his new book Flour + Water: Pasta and we started by asking him the basics: what’s really the best way to cook pasta? As it turns out, the answer is more nuanced than you’d think — and there are plenty of ways to improve on something you’ve been doing the same way for years.
The final cooking step for pastas at flour + water is very quick, usually less than five minutes. Most of the time-intensive work comes in the prep work: making the pasta, making the braised meat for the sauce, slicing the vegetables, and so on. Nearly all the dishes can be prepped ahead of time and then cooked or “assembled” or both when ready to eat. (Not to mention, you can swap out dried pasta in many of the recipes.)
Our pasta dishes in the restaurant—and the book—are nearly always finished with a version of a pan sauce, made à la minute. Now, usually when I say the words “emulsified butter sauce,” home cooks freak out and get intimidated. Please don’t. The sauce is simply butter that has been melted to coat and accentuate the accompanying ingredients.
The entire philosophy of pan sauces is simple: the starting point of any sauce is thinner and wetter than the finished product. As the sauce reduces to the perfect consistency, it’s also cooking the pasta.
The trick, however, is timing. The sauce is reducing while the pasta is cooking, so the goal is to bring both components to perfection at the same time. It’s a balancing act.
A pan sauce has achieved the proper sauce-like consistency when it is thick enough to coat the back of a spoon. At that moment, the bubbles in the pan will be getting larger and the bubbling will slow down as the sugars and starches begin to thicken to the perfect level. If you run a spoon along the bottom of the pan, the sauce should have enough structure that it holds for a moment, but enough fluidity that it eventually oozes back into the spoon’s line. (If the sauce gets too dry before the pasta is completely cooked, a splash or two of starchy pasta water can be used to “reset” the sauce.)
The reality of the science is that once pasta is cooked in water, it doesn’t absorb any more flavor from the finishing pan sauce. Because pasta is water-soluble, it absorbs only the water from the sauce, not any aroma or oils. Instead, the pasta is adsorbing the flavors, meaning the flavor only sticks to the surface of the pasta. That simple tidbit of information blew my mind when Harold McGee, the San Francisco–based author of On Food and Cooking (one of my all-time favorite books), explained it. For years, I had been teaching cooks that finishing pastas in pan sauces helped noodles absorb flavor, but as it turns out, that false impression comes from the amount of sauce that adheres to the surface of the pasta.
Give us an overview of your 80-20 rule for cooking pasta.
We cook pastas 80% in starchy water and 20% in sauce. We’re always finishing them in sauce. At home, add a little scoop of semolina in your pasta water just before you cook the pasta.
You swear by reserved pasta water. What role does it play?
Starchy water helps stabilize the sauce; it’s a thickening agent. That’s a trick of the trade.
We have these giant pasta cookers, which are incredibly enriched with starch. You don’t add too much salt to the dough itself because salt denatures the eggs. But salt is really important. When I’m tasting for how the dish is seasoned, I can taste a noodle or stuffed pasta and say, you need to add a scoop of sea salt to your water. In stuffed pastas, you want your fillings highly seasoned.
In pasta, your cooking water should be slightly less salty because you’re using that water for sauces as well. You don’t want it too intensely salty, because as you reduce it down, the salt content will stay the same as the water evaporates.
How do you use butter to finish a dish?
On a not-so-busy night we use 20 pounds of butter. A lot of stuffed pastas are all about the filling and the noodle, and we want that to shine. It’s a northern Italian thing to finish a dish in just a butter emulsion: starchy pasta water and butter. It creates a velvety mouthfeel that lets the filling shine. We don’t really use a lot of complicated sauces with stuffed pasta.
What’s your perfect definition of al dente? How can you tell when your pasta is there?
With risotto and pasta, there’s this macho-ism with al dente. People are crunching down on noodles. I hate an undercooked noodle! It’s not fun to eat, for one thing, and then there’s raw dough sitting in your stomach. What I tell our cooks is that you want it to the point where it has the most mouthfeel to it, the most possible texture it can have, but it’s finishing clean on your palate. As you’re chewing, it shouldn’t be sticking to your teeth – that’s too undercooked.
If you take out a noodle or piece of dough and bite in, you don’t want to see anything white. That inner ring of white – that white part is raw dough.
Tajarin is the thinnest noodle we make. It’s small and thin and can overcook in seconds. It’s always great, if you’re questioning yourself, to pull a noodle from the pasta cooker earlier rather than later. If you’re cooking it in sauce, you can thin out the sauce with pasta water or chicken stock or olive oil.
What are the most common mistakes people make when making pasta at home?
The number one thing – which is still the way my mom cooks – is to never boil spaghetti, put it in a bowl, and pour the sauce on top of it. What you have is dry noodles that stick together, and a sauce – there’s no marriage of the starch. Always cook the noodle in a pan.
And tasting – a lot of people don’t taste. Every stove cooks completely differently, and there can be big differences in a rapid boil versus a slow simmer. Taste, taste, taste.