Cooked slowly in heavy cream with herbs and spices, these mushrooms acquire a deep and unusual taste. They are truly delicious; thick, smooth and very rich and will taste equally wonderful served with egg noodles, like Beef Stroganoff is served in America or with shoestring French fries like we used to serve it in Europe or over Creamy Polenta and sprinkled with Gruyere or Cheddar cheese with Truffles. The possibilities are endless and all scrumptious.
Heat a large sautéing pan on medium-high heat, add 1 tablespoon of the oil and 1 tablespoon butter; add mushrooms, in portions.
Season lightly with salt and pepper. Cook the mushrooms until they are really well browned; then transfer them to a bowl.
Add to the pan the remaining oil and butter; thinly sliced onions and a little more salt and pepper. Sautee the onions on medium heat stirring often, for about 20 minutes or until they are a rich golden- brown color; then add garlic and cook, stirring, for a couple more minutes.
Add the flour and stir until fully incorporated.
Deglaze the pan with Sherry, add back the browned mushrooms.
Simmer uncovered for 10 minutes, then add beef stock and coffee; continue cooking until the sauce is reduced and thickened.
Pour cream over the mushrooms.
Tie parsley and dill sprigs, peppercorns, cinnamon stick, bay leaves and cloves into a cheesecloth sachet and add to the pan with the mushrooms.
Cover and simmer the mixture for 40- 50 minutes, or until the liquid is absorbed. Remove the cheesecloth sachet and serve.