Peel or clean the onion and vegetables. Wash, chop and fry in 40 g butter. With flour
dust, sweat briefly. Stir in broth and wine. Season with salt and pepper. Bring to the boil, simmer for 15 minutes
Dice bread and roast in 1-2 tablespoons of hot butter. Dust with cinnamon and mix
Sieve the soup. Add cream and bring everything to the boil. Finally, alloy with egg yolk (do not let it boil any more!). Season with salt, pepper, nutmeg and sugar. Serve the mustard soup with the croutons