Cut the meat into large pieces and season with salt. For the marinade: Slice the onions, carrots, and peppers into rings, dilute the tomato paste with warm water, sprinkle the meat with red pepper, and coat it with mustard. Pour in the wine, add the tomato paste, vegetable rings, and bay leaves. Let the meat marinate in the fridge overnight. Preheat the oven to 200°C. Place the meat with the marinade into a casserole dish and add enough water to cover the meat. Cover with parchment paper and aluminum foil. Close the lid and bake at 250°C for 1 hour. Lower the temperature to 200°C and bake for another 2 hours.