Steam cauliflower 18 minutes or until tender but not mushy. Set aside.
Cook the carrots in the evaporated milk and water, covered, in a medium saucepan, 10-15 minutes or until very soft. Place the carrots and cooking liquid, mustard, Worcestershire sauce, and lemon juice in a blender, and whiz for 2-3 minutes or until smooth and glossy. Add the salt, cayenne, and cumin, and whiz to mix.
Place the cauliflower in a small baking dish. Spoon the carrot sauce over the cauliflower and scatter the Parmesan cheese over the top. Brown under a preheated broiler 4 inches from heat and serve, garnished with a dusting of smoked paprika.