In a large saucepan over medium heat, melt the butter with the remaining 1 tablespoon olive oil. Add the garlic and anchovies and cook, stirring, until the garlic is lightly golden and the anchovy dissolves, 2 to 3 minutes. Add the red pepper flakes, then stir for 1 minute. Add the breadcrumbs and toss for 3 minutes to coat and toast them a bit. Add the olives, raisins, and capers and cook, stirring, until just warm, about 1 minute. Gently fold in the roasted cauliflower and 4 cups of the cooked pasta. Add up to 1 cup of the reserved pasta water, 1/4 cup at a time, gently tossing until a nice sauce forms. Add the cheese and parsley and toss to combine. Season to taste with salt and pepper and serve.