PREHEAT OVEN TO 190 degrees C, or according to cannelloni packet instructions.
Use a food processor to chop leek and medium onion very finely. Heat some olive oil in a pan and fry them until softened. Add the mushrooms and cheese, and cook, stirring until the vegetables are golden. Once the cheese has melted into the mixture, remove from heat and leave to cool.
Meanwhile, in a separate fry pan, fry the small onion in a little oil ,until brown. Stir in tomatoes. Mix stock cube with hot water and add to onion and tomatoes with the worchestire sauce. Cook the mixture until reduced by half. Fill the cannelloni with the leek and cheese mixture and place them in a greaseproof ovendish. Pour over the tomato sauce and bake for 25-30 mins.
just posting for Joh