1 12-16 oz head of cauliflower
1/2 cup walnut pieces
1 tin oil-packed anchovy fillets
1 clove garlic
1 bunch flat-leaf parsley
1/4 cup extra virgin olive oil, plus 4 tablespoons
1 pound dried spaghetti
1/4 cup grated parmigiano-reggiano, plus more to taste
freshly-ground black pepper
Cut the cauliflower into florets, place into a food processor and pulse to form pieces about the size of large breadcrumbs and dump into a mixing bowl.
Place walnuts, anchovies, garlic, parsley, 1/4 cup olive oil and jalapeño in the food processor and pulse until smooth paste is achieved. Add 1/4 cup parmigiano-reggiano, pulse briefly, then add mixture to cauliflower. Set aside.
Bring 6 quarts of water to a boil and add 2 tablespoons salt. Drop pasta in and cook according to package instructions.
Heat a large sauté pan over medium heat and add remaining olive oil. Add the cauliflower mixture and cook 5-6 minutes until light golden brown. Remove from heat and set aside
Remove the pasta from the water with a spider or tongs, reserving some of the pasta water, then add the pasta to the pan with the cauliflower mixture and toss over medium heat until well coated, about 30 seconds. Ladle pasta water into the pan to loosen the sauce, as needed.
Remove from heat, toss in the remaining parmigiano-reggiano and mix well, then pour into a heated bowl, season with freshly ground black pepper, and serve immediately.