Brown beef in a fry pan, add herbs, vinegar, tomato paste, Worcestershire sauce, stock cube and 1 cup boiling water. Simmer for 10 mins. Slice potatoes and pumpkin and partially cook in the microwave or by boiling. Slice the onions and tomatoes. Layer in a large casserole dish (a few times each) meat, potatoes, pumpkin, onions, tomatoes and top with the grated cheese. Bake in a moderate oven for about 1 hour.