From the NY Times. Actually, Romanesco Broccoli is a form of bright chartreuse cauliflower with pointy spiral florets. He says it's fine to substitute regular cauliflower.
Ingredients
Salt and pepper
2 or 3 medium heads romanesco broccoli (about 3 pounds), or substitute Cauliflower
3 tablespoons extra-virgin olive oil, plus more for baking dish
1 pound fresh mozzarella, sliced
1 cup grated pecorino or Parmesan (about 2 ounces)
1 dozen soft black oil-cured olives, or another type of black olive, pitted
1 teaspoon roughly chopped capers
4 roughly chopped anchovy fillets
4 garlic cloves, minced
½ teaspoon crushed red pepper, or to taste
Pinch of dried oregano
Instructions
1. Put a large pot of well-salted water over high heat and bring to a boil. Heat oven to 375 degrees.
2. Cut broccoli into quarters and trim away the core and any tough bits. Chop quarters into rough 2-inch cubes. Transfer to boiling water and cook for 2 minutes. Drain and rinse with cool water.
3. Lightly oil an earthenware baking dish. Arrange blanched broccoli in one layer. Season lightly with salt and pepper.
4. Tear mozzarella slices and scatter over the top, then sprinkle with pecorino. Arrange olives here and there. In a small bowl, stir together capers, anchovy, garlic, red pepper and 3 tablespoons olive oil. Drizzle mixture evenly over the top.
5. Bake for about 30 minutes, until cheese has browned a bit and broccoli is tender when pierced with a fork. Let rest 10 to 15 minutes before serving. Sprinkle with a good pinch of dried oregano.