Tip the tomatoes and bean salad into an ovenproof frying pan or shallow flameproof casserole dish. Simmer for 10 mins, or until reduced. Stir in the spinach and cook for 5 mins more until wilted. 

Heat the grill to medium. Make four indentations in the mixture using the back of a spoon, then crack one egg in each. Nestle the ham in the mixture, then grill for 4-5 mins, or until the whites are set and the yolks runny. Serve with rye bread, if you like.