3 Tbsp. extra-virgin olive oil
1small onion, finely chopped
Kosher salt
6 garlic cloves, thinly sliced
¼ cup double-concentrated tomato paste
12 oz. mixed mushrooms (such as cremini, shiitake, oyster,
and/or maitake), tough stems trimmed, coarsely chopped
¼ cup heavy cream
Freshly ground black pepper
12 oz. rigatoni or other short pasta
2 Tbsp. unsalted butter
1oz. Parmesan, finely grated (about ½ cup), plus more for
serving
Heat oil in a small pot or large saucepan over medium. Add
onion and a big pinch of salt. Cook, stirring occasionally, until onion is very
soft, 6–8 minutes. Add garlic and cook, stirring often, until softened and
beginning to turn golden around edges, about 4 minutes.
Add tomato paste to pot and cook, stirring constantly, until
slightly darkened in color, about 1 minute. Add mushrooms and season with more
salt. Cook, stirring often, until softened, 6–8 minutes.
Add cream and 1 cup water, increase heat to high, and bring
to a boil. Reduce heat and simmer, stirring occasionally, until ragù is
slightly thickened, 13–17 minutes. Taste and season with pepper and more salt
as needed.
Cook pasta in a large pot of boiling salted water, stirring
occasionally, until very al dente, about 2 minutes less than package
directions. Drain, reserving 2 cups pasta cooking liquid.
Add pasta, butter, 1 cup pasta cooking liquid, and 1 oz.
Parmesan to ragù. Cook, tossing and adding more pasta cooking liquid by
¼-cupful as needed, until sauce coats pasta and pasta is al dente, about 2
minutes.
Divide pasta among shallow bowls or plates and top with more
Parmesan.