Place a small saute pan in the mouth of the oven with 1⁄4 cup oil and the anchovies. Heat for about 2 minutes to dissolve anchovies, stirring as needed. Do not burn. Smash garlic clove with the tip of a knife, finely chop, and add to saute pan along with red pepper flakes. Cook for about 1 minute; remove and set aside. Rinse cauliflower and remove the green leaves at the base. (Do not remove the solid core). Set cauliflower upright on a cutting board and slice in half lengthwise. Slice each half into 1⁄4-inch slices. Set sliced cauliflower on a sheet pan, drizzle with remaining oil, and toss well to coat. Set in the oven and roast for 10 minutes. Remove and add anchovy sauce and pecorino, mixing well. Return to oven for 3–5 minutes more, or until tender with browned crisp edges. Remove, sprinkle with parsley, and serve.