Step 1

Roughly chop cauliflower stems and florets. Transfer to a large pot, fill pot with water, season generously with salt, and bring to a boil. Reduce heat to a simmer, and cook, uncovered, until cauliflower is very soft, about 10-12 minutes. Do not drain.

Step 2

Using a slotted spoon, transfer half of the cauliflower to a food processor or blender, along with a 1/2 cup of the cauliflower cooking liquid, half of the garlic, half of the lemon zest, half of the red pepper flakes, a third of the Parmesan cheese, and 2 tablespoons olive oil. Leaving an opening at the top of the blender so steam can escape, blend until smooth and creamy, about 1 minute. Transfer mixture to a large bowl. Repeat with remaining cauliflower, garlic, lemon zest, red pepper flakes, another third of the Parmesan cheese, and another 2 tablespoons olive oil. Transfer to the bowl with the rest of the sauce. Taste the sauce and season with salt and pepper as desired.

Step 3

Heat the oven to 425℉. To the now-empty pot, add additional water as needed to cook the pasta. Bring the water to a boil, season generously with salt. Add the pasta and cook until very al dente, about 2 minutes less than package instructions. Drain pasta and add to the bowl with the cauliflower sauce, toss gently to coat. Taste the mixture again and season with salt and pepper as desired.

Step 4

Transfer the mixture to a 9x13-inch baking pan. In a medium bowl, combine the panko, parsley, remaining Parmesan, pinch of salt, and remaining 2 tablespoons of olive oil. Sprinkle it on top of the cauliflower pasta. Bake for 20-25 minutes, until the sauce bubbles slightly around the edges and the breadcrumbs are browned on top. Let stand for 15 minutes so you don't burn the roof of your mouth when you take a bite, then dive right in.