• Remove the stems from the mushrooms; finely chop the caps.
• Peel and finely chop the shallot.
• Scrub or peel the carrot; cut it into quarters lengthwise, then cut the quarters into ¼-inch pieces.
• Cut the celery in half lengthwise, then cut the halves into ¼-inch pieces.
• Rinse the black lentils.
• Finely chop, press, or grate enough garlic to measure 1 teaspoon.

In a medium sauce pot over high heat, warm 1 to 2 tablespoons oil until hot but not smoking. Add the mushrooms, season with salt and pepper, and cook, stirring once or twice, until lightly browned, 3 to 4 minutes. Add the shallot, carrot, celery, lentils, and garlic and cook, stirring occasionally, until starting to soften, 3 to 4 minutes.
Add the vegetable stock, tomatoes, tomato paste, and as many chile flakes as you like. Bring to a boil, reduce to a simmer, cover, and cook, stirring occasionally, until the lentils are soft, 18 to 20 minutes. Remove from the heat, cover, and keep warm.
While the sauce cooks, prepare the pasta.

Bring a medium sauce pot of generously salted water to a boil. Add the fusilli and cook until just tender, 8 to 10 minutes. Drain.

• Strip the parsley leaves from their stems; coarsely chop the leaves.

Add the drained fusilli to the pot with the sauce. Add 1 tablespoon oil and half the Pecorino and stir to combine. Season to taste with salt, if needed.

Transfer the pasta to individual bowls or plates. Garnish with the parsley and pass the remaining Pecorino at the table.

Chef's Tip If you have a food processor, in Step 1, instead of chopping the mushrooms, shallot, carrot, and celery, pulse all of them together a few times with the blade attachment, then proceed with the recipe. Or, if you prefer an even finer-textured sauce, grate them with the grater attachment.