I have adapted this recipe closely from the New York Times recipe. I love the addition of the pommerey mustard and the cognac. It lends great flavor to the broth and a lovely velvety thickness. Allowing the beef to simmer for a long time is the key to the stew as the meat breaks down the longer it stews. I think adding the carrots at the end, and sautéing the mushrooms, and adding them at the end helps them retain their integrity. I have reprinted the basic recipe courtesy of the New York Times.