Clean the cauliflower and cut into florets. Cook in a little salted water for 5 - 6 minutes until al dente. Meanwhile, peel and roughly grate the carrots.
Briefly sweat the carrots in the butter, add the cauliflower. Mix the mustard, milk and cream and add to the vegetables. Bring to the boil briefly. Season to taste with salt, pepper and turmeric. Serve sprinkled with cress.