Cook the pasta in well-salted water to al dente. Before draining, scoop out 1 cup of the pasta water — it's the key to a silky sauce.

While the pasta cooks, blend the cottage cheese, half the parmesan, lemon juice, salt, and pepper until completely smooth, about 45 seconds.

In the empty pasta pot, warm the olive oil over medium-low and cook the garlic and red pepper flakes 60 seconds, until fragrant.

Add the spinach and stir until just wilted.

Turn the heat to LOW, return the pasta, pour in the blended sauce, and toss with a splash of pasta water until glossy. Do not let it boil — high heat makes the sauce grainy.

Serve with the remaining parmesan and more black pepper.