White onion soup comes from England and is much easier to make, creamy, or if you prefer, puree soup. But here, unlike other puree soups, the thickening is based on Roux and Béchamel sauce. Due to the milk in the composition, the soup acquires not only a creamy consistency, but also a creamy, slightly sweet flavor.The soup is served garnished with cream and finely chopped parsley greens, but can also be served with pan-fried croutons, with olive oil.
Cut the onion and celery into small cubes. Take a deep frying pan, pour 1 tbsp of water and add a little butter, heat the pan and add the onions and celery. Cover with a lid and simmer until soft.
Transfer the contents of the pan to a food processor or blender, puree until smooth.
Add the remaining butter to the pan, melt. Add the flour. Constantly stirring, cook the roux (more on that here). Pour in milk a little at a time and stir constantly with a whisk until you have a smooth, thick sauce.
On a separate burner, heat the chicken broth. Pour it into a deep pan with the sauce and add the mashed onions and celery. Bring to a smooth consistency, stirring constantly.
Grate the nutmeg and season with salt and pepper, to taste.
Pour onto plates, serve with cream and finely chopped parsley greens.