1. Place all the ingredients except the beef kidneys in an oven-proof casserole dish and bake in a 325F oven for 3 hours.
2. If you are using a powdered demi-glace, reconstitute it with water as directed on the package.
3. When the brisket is fork tender, remove from the oven and place the meat in a separate bowl to cool. When you can handle the brisket, flake the meat with your fingers. You may have to cut the meat into some smaller pieces to do this easily.
4. Bring the sauce to a boil on the stove and reduce by 1/3 or until the sauce is slightly thickened.
5. Cut the kidneys into small pieces (1” X 1” approximately). Mix the meat back into the sauce with the kidneys.

1. Thoroughly combine flour, baking powder and salt in a mixing bowl.
2. Remove butter from the freezer just before use and grate directly into the flour mixture using the large size of a box grater.
3. In a separate bowl, mix iced water, egg yolk and vinegar together. Add to butter/flour mix and just bring together. Do not knead more than necessary.
4. Wrap in plastic film and allow to rest for 90 minutes in refrigerator before using (overnight is best).

1. Trim the stems off the mushrooms so just the cap remains. Quickly rinse the mushrooms under running water just before making the recipe, but not in advance.
2. Bring all the remaining ingredients to a boil and throw in the mushrooms. Bring to a boil and simmer for 5 minutes.
3. Remove from the heat and rest until the mushrooms reach room temperature. Remove the onion halves and serve.

The mushrooms can be kept refrigerated for several weeks or preserved using a standard jarring procedure.

1. Try to use a casserole dish sized such that the meat and sauce come almost to the top.
2. Roll out pie dough in a piece large enough to cover the casserole dish. (Dough recipe can be found below.)
3. Brush the top of the dough with a little eggwash or cream. Trim the edges if desired, though leaving some over the dish will create lovely browned, crunchy pieces that taste great!
4. Bake in a 350 F for 35 to 40 minutes. Let stand for 10 minutes before serving.

Note: These can be made in small, individual ramekins as well, or as a turnover.