I’ve heard people say they don’t like onions. This seems impossible. Onions are an essential ingredient in nearly every savory dish. Sautéed, onions are so flavorful that adding just one to canned tomato sauce will enliven a midweek pasta. Perhaps thanks to this ubiquity, the onion is not the flashiest ingredient, the kind of distinctive keynote preceded by adjectives on restaurant menus. But I agree with Jasper Johns: “If truffles and onions cost the same amount of money, you would obviously choose an onion. You don’t need truffles; you do need onions.”
This savory and, if need be, vegetarian pasta brings onions to the fore. Caramelizing onions is an easy, if time consuming, technique that coaxes out their sweetness. Be patient. The long, low heat breaks the biting, complex carbohydrates down into nutty, browned simple sugars. Caramelized onions are so packed with flavor that this dish would be quite tasty even if the mushrooms were omitted.
The onions provide so much heft that there isn’t much need for a sauce. Cook the pasta slowly in stock, just as you would treat rice when making a risotto. This technique produces soft pasta and a rich broth. Dried pasta has an enormous capacity to absorb its cooking liquid, which is usually salted water. When cooked slowly, it retains its starch and becomes unusually creamy. I like to use chicken stock, but a vegetarian version of the dish is equally delicious.
Sautéing some mushrooms before adding the pasta and stock gives this dish an earthy flavor. Eastside Marketplace has a great selection of wild mushrooms, which are fun to experiment with, but even white button mushrooms would work. If you want to skip the mushrooms altogether, start with the pasta and liquid directly.
Risotto-style gemelli with caramelized onions and wild mushrooms
90 minutes, serves 4-5
4 large yellow onions
1/3 lb. shiitake mushrooms
1/3 lb. oyster mushrooms
1 lb. gemelli (or other short pasta, like penne or fusilli)
1.5 qt. stock (this can be chicken or vegetable stock)
3 garlic cloves, minced or pressed
3 Tbsp. dry white wine or dry vermouth
3 Tbsp. olive oil
crushed red pepper flakes
chopped parsley (optional)
Peel onions and slice into thin rings (about 1/8” thick). Using a mandoline or a food processor’s slicing blade will make this go quickly, and rinsing them after cutting off the ends and peeling will cut down on the crying. Clean mushrooms with a damp paper towel, being careful not to saturate them with water. Cut off shiitakes’ stems, and slice the caps about 1/3” thick.
In a large pot with a tight-fitting lid, cook the onions over medium-low heat for 10 to 15 minutes, stirring occasionally to ensure even cooking. If you have an extractor hood over your stove, definitely turn it on. The onions will start to sweat, giving off a lot of liquid, which will keep them from sticking. Season liberally with salt and black pepper.
When the onions turn golden and are just beginning to stick to the bottom, add 3 Tbsp. olive oil and continue cooking, covered, over medium heat for approximately another 10-15 minutes. Taste them regularly. The longer the onions cook, the more caramelized they will become, gradually losing their sharp, oniony flavor.
When the onions are finished cooking, put them on a covered plate to keep warm. Without cleaning the pot, add the last tablespoon of olive oil and sauté the mushrooms and garlic. Add the shiitakes first, followed two minutes later by the oyster mushrooms and garlic. At first, the mushrooms will absorb the oil, and the pot will appear to be dry. As they continue to cook, they will release the oil back into the pot along with their own liquid.
Pour in the white wine to deglaze the pot. Scrape the pot with a spatula or wooden spoon to dissolve the flavorful bits of onion stuck to the bottom. Let the alcohol cook off for a minute or two before moving on to the next step.
Add the pasta and stir to coat with the oil and wine. Add just enough stock to nearly cover it. Cook, covered, over medium-high heat, stirring occasionally. The pasta will absorb the stock, gradually softening. Continue adding stock in quarter-cup increments to keep the pasta mostly submerged. When it is finished cooking, after about 30 minutes, the pasta should be completely soft and the stock should have reduced to a thick, flavorful broth. If the stock runs out midway, you can finish cooking with water. Put the caramelized onions back into the pot a few minutes before the pasta finishes cooking so they have a chance to warm back up.
When the pasta is finished, season to taste with salt, black pepper, and crushed red pepper flakes. Mix in some chopped parsley and Parmesan cheese. Serve immediately.