Slice the celery and leek finely. Chop the unblanched sprouts in half. Heat the olive oil and fry the onion, celery, leek, garlic and the sprouts gently without allowing them to brown. Add the vegetable stock, then the cream and leave to cook gently until the sprouts are tender. Halve the shallots and then again lengthwise. Fry them gently in a pan and use them as garnish. Slice the smoked sausage thinly and dry the slices in the oven for 2.5 hours at 100°C. Puree the soup and season with salt and pepper. Season the crème fraîche with the yellow curry. Shape the crème fraîche into quenelles and serve them in the soup. Stick a few smoked sausage crisps into the crème fraîche, garnish with the shallots and the blanched sprouts.