Over medium heat, heat oil in a large pan. Cook and stir mushrooms and shallots for 4 minutes.
Using a clean pan, spray with cooking spray or add a few drops of oil and heat until hot. Put lemon peel and pepper on beef steaks and press.
Cook steaks from medium rare to medium for 12 to 15 minutes, turning occasionally. Remove from the heat and keep warm.
Add the brandy to the pan and cook and stir until all browned bits have dissolved.
Add the half-and-half, mustard, Worcestershire sauce, and lemon juice. A mixture of mushrooms is added; heat thoroughly.
