The onion cream soup can be as simple or as complicated as you want it to be. I prefer the simple version of everything in life, so, although I could give you the complicated recipe, I will give you the simple one. And as a bonus, the trick that differentiates a good onion cream soup from an awful one.
For six servings, you need about half a kilogram of white onions, 100 grams of butter (awful!), 300 milliliters of milk, 150 milliliters of cooking cream, 300 milliliters of water and a good blender. A few coriander seeds, a pinch of nutmeg, a pinch of cinnamon, salt and a good knife will also help.
Dice the onion and put it on low heat with the melted butter in which you dropped 2 drops of oil (they go well together and one prevents the other from burning too fast). Here comes the trick: soften the onion on low heat for at least a quarter of an hour, or better yet, for 20 minutes. This makes the difference between a tasty, flavored, sweet, pleasant and fine cream and a terrible dish, tasting like scalded onion. The onion has to transform itself into a sauce and only then you can add the milk. Also add the water. Let it simmer and add the spices grounded in a mortar.
After it has reduced to your liking, mix it with a blender (either vertical or the “kitchen machine” type), pour it through a fine sieve, put it on the stove again and add the cooking cream. It’s done after another three minutes on low heat. Mind the salt. Stay healthy.