1½ cups lightly packed cilantro
½ cup lightly packed parsley
¾ cup walnuts
2 garlic cloves
½ cup olive oil, divided
Kosher salt and freshly ground black pepper
Pinch of red pepper flakes, optional
12 ounces pasta (We used casarecce.)
1 small head of cauliflower (1½ pounds), cut into 1-inch florets (about 4 cups)
1 small red bell pepper, cut into ¼-inch wide strips
1 small yellow bell pepper, cut into ¼-inch wide strips
Combine the cilantro, parsley, walnuts and garlic in the bowl of a food processor. Pulse until finely chopped. With the food processor running, drizzle in 6 tablespoons of olive oil. Season with salt and pepper to taste, and add the red pepper flakes if desired.
Cook the pasta, according to package directions, in a large pot of boiling salted water. Drain, reserving ¼ cup of the pasta water.
While the pasta cooks, heat the remaining 2 tablespoons of oil in a large skillet over medium-high heat. Add the cauliflower and a generous pinch of salt and cook, stirring occasionally, for about 5 minutes until browned in spots. Add the peppers and continue cooking, stirring occasionally, another 5 minutes.
Remove from heat and add the pasta, pesto and reserved pasta water. Toss to combine. Season with additional salt and pepper, if needed.