Preheat oven to 200/400° C/F.
Prepare a baking sheet lined with foil. Coat cauliflower florets with olive oil and spread them out on the baking sheet in a single layer.
Bake at 400°F for 15 to 20 minutes.
In a small saucepan, add all the sauce ingredients. Heat for about 5 minutes over medium heat until melted and smooth, whisking frequently. Keep warm over low heat while you wait for the cauliflower to bake.
In a mixing bowl, toss roasted cauliflower with the sauce until well-coated.
Serve in bowls. Evenly sprinkle Parmesan cheese on top and season with freshly ground black pepper.