Prepare 2 liters of chicken stock by boiling 2 liters of water with the stock cubes.
Melt the butter in a frying pan and add the chopped onion half. Cook for 2 minutes, then add the chestnuts and the grated garlic. Cook for a further 3 to 4 minutes, and then deglaze with the cognac for 1 to 2 minutes. (Whiskey can substitute for cognac if necessary.)  Proceed on medium heat.

Put aside one medium-sized mushroom per person and a few chestnuts.

Clean the rest of the mushrooms, chop them coarsely, and add them to the chestnuts. Add the sprigs of thyme, the paprika, the ginger, the stock and some salt.

Cook on medium heat for 30 minutes covered, plus 15 minutes uncovered.

Whip up the cream (unsweetened) and reserve in the refrigerator.

Ten minutes before the cooking ends, heat the oil in a pan. Fry the cèpes that have been reserved, having first cut them in two and having crosshatched them with the knife (cut side down first, for 5 minutes, then 5 minutes on the other side). Salt.

After the cooking, remove the thyme sprigs, blend with a stick blender, and then pass the mix through a food mill.
Add half of the orange zest, taste, adjust the seasoning, pepper, and add more zest according to taste.

Place the mushroom halves on the plates with a few chestnuts. Pour over the velouté and add a dollop of whipped cream.

Now serve!