Hull the spinach, wash it and chop it into a chiffonade. Immerse them in boiling water then drain and wring them out. Pat this cloth dry over a medium heat. Gradually add, while stirring, 80 g of margarine and 1 cc of powdered sugar. Salt and pepper lightly. Simmer over low heat, without covering.
Peel and finely chop the shallots. Make them
melt in 50 g of margarine, without making them color too much. Add plenty of salt and pepper. Add the sugar, Worcestershire sauce and vinegar. Increase the heat for a few seconds then reduce again. Then add the mustard and simmer over very low heat, without covering until you obtain a jam.
Cut the meat into large cubes. Heat the oil in the pan. When the oil is hot, everyone cooks their meat to their liking, garnishing with shallot and spinach jam.
Suggestion: serve the fondue with a green salad.