2. Fill the plastic bag with 1 cup seasoned flour, place ribs in it, seal and shake well; ribs must be well-coated.
3. In a medium mixing bowl, whisk together the sherry vinegar, tomato paste, soy sauce, chili sauce, sugar, cayenne pepper. Dip the ribs with flour in this marinade and refrigerate for at least 30 minutes and then place in the Air Fryer basket. Set your Air Fryer to 400 F and cook the ribs for 15 minutes, turn the ribs halfway through cooking time to cook evenly.
4. To prepare the sauce: Cook the onions in butter over medium flame, then stir in flour and beef stock. Cook for 5 minutes over low heat. Then add the Madeira and cook further 3-4 minutes, over medium-high heat.