For the filling, mix together the cheese, green pepper, onion, sweetcorn, salt, pepper, and tomato sauce. For the paste, mix 2 tablespoons of flour in 2 tablespoons of water to make a thick lump free paste.
For the samosa, lay flat on a work surface then fold the bottom left hand corner up in to a diagonal so that you have a point of a triangle on the left hand side. Then take the bottom right hand corner, and fold completely to the left hand side. You should have a secure sealed pocket.
Once done, add a spoon full of filling and seal the samosa by adding some of the 'glue' to the left over pastry hand and folding over to seal the samosa. Make sure the samosa is completely secured.