Sunflower-Seed Pesto Pasta

From the garden

• ½ cup hulled raw sunflower seeds, toasted
• 2 cups fresh basil leaves, packed
• 1 clove garlic

From the pantry

• ½ cup parmesan, finely grated — plus more for serving
• ½ cup olive oil
• 1 lemon — juice of half, or to taste
• 1 lb pasta
• salt

1. Toast the sunflower seeds in a dry skillet over medium heat, 3–4 minutes, shaking often, until golden and nutty-smelling. Cool a few minutes.
2. Bring a large pot of well-salted water to a boil and cook the pasta to al dente. Before draining, scoop out a cup of the starchy water.
3. While the pasta cooks, pulse the seeds and garlic in a food processor to coarse crumbs. Add the basil and parmesan and pulse, streaming in the olive oil, until you have a thick, slightly coarse paste. Season with salt and a squeeze of lemon.
4. Toss the hot pasta with the pesto off the heat, adding pasta water a splash at a time until a glossy sauce clings to every piece — never simmer pesto, or it dulls to olive-drab.
5. Serve immediately with extra parmesan and a last grind of pepper.