Season the chops with salt and pepper, roast in the butter on both sides for 5 min. each, keep warm.
Quarter the onions, cut the green into 3 cm long pieces.
Clean rhubarb and also cut into 3 cm long pieces.
Caramelize sugar in hot butter.
Add onions and rhubarb, steam briefly until soft.
Extinguish with soy, vinegar and vegetable soup, simmer on low heat for 5 min. with lid closed.