Preheat the oven on 160 degrees Celsius or 320 degrees Fahrenheit.
Peel the potatoes, cut them in half and cook for about 25 minutes.
Divide the cauliflower in four 'steaks'. Cover the cauliflower with some seasoning and olive oil. Place on a baking tray and roast for about 30-40 minutes.
Cut the onions and garlic in slices and bake in the 50 grams of butter on a medium heat. When the onions are brown and caramelized, add the stock and let it cook for 5 minutes. Then add the cream. Blend the sauce until smooth. Pour through a fine sieve to make sure all the lumps are removed.
Make a puree of the potatoes by mashing the potatoes with the milk, butter, salt and pepper and a pinch of nutmeg. Keep warm in the cooking pan.
Toast the almond chips in a baking pan (or the last 5 minutes in the oven with the cauliflower).
Heat some sunflower oil or olive oil in a pan and bake the capers crispy.
Serve the cauliflower on top of some potato puree with the sauce, almonds and capers.