Chop the bacon or ham and fry it to release the fat. Remove the pieces from the pan and drain on some paper towel.

Add some butter to the pan and brown the chicken legs. Set them aside and brown the pickling onions till darkened. Remove the onions too.

Saute the chopped onions and garlic, add the flour and oregano to brown, then deglaze with water and wine.

Put all the prepared ingredients into the pressure cooker. Add the stock and deglazing liquid to make sure there is enough liquid and cook in the pressure cooker for about 10 minutes.

Allow the pressure to return to atmospheric.

Carefully remove all the meat and onions etc with a slotted spoon into a warmed serving dish.

Reduce the remaining liquid by boiling rapidly, adding the coarsely chopped mushrooms a short time before the end.

When the sauce is judged to be suitably reduced, adjust the seasoning to taste, and pour it over the meat and onions in the serving dish.

Vive la France!