Put the cauliflower flowerets in a steamer, season with salt, and steam until just tender, about 10-15 minutes depending on the size and age of the vegetable.
Meanwhile, in a small pot, sauté the garlic and peperoncino very gently in the olive oil. The heat should be as low as you can manage, so that the garlic and peperoncino steep more than they cook in the oil. When the garlic is slightly brown, add the anchovies and capers and continue to cook very gently, until the anchovies have fallen apart. Add a splash of white wine or water; you will see the anchovies instantly dissolve. Turn off the heat and add most of the chopped parsley. Keep warm, covered, until you're ready to use.
When the cauliflower is done, arrange the flowerets on a warmed serving dish. Nap each floweret with a bit of the anchovy sauce, and pouring any extra sauce around the base. Sprinkle the top with some extra parsley for color, and serve immediately.