How to make
Finely chop the onion and garlic and cut the celery head into small cubes. Stew the vegetables in a pot with a little fat and add the chicken broth. Season with fresh thyme, nutmeg, cayenne pepper, bay leaf, salt and black pepper.
Wait for the broth to boil and add the flour. Stir and gradually pour the milk. Stir the mixture at all times, so that no lumps form. Again, gradually and with constant stirring, pour the beer.
Grate the cheddar cheese and add it to the mixture. Stir, until it has melted and remove the soup from the heat.
In another pan, heat the butter and stew the red onions. Cut the baguette in half lengthwise and bake it in the same pan.
Serve the soup garnished with the toasted bread and caramelized onions.