First make the relish, soften onion in olive oil Add sugar & vinegar then reduce to a syrup Add diced tomato & passata, reduce to a thick consistency Keep to one side Gently fry sausage in a non - stick pan over medium heat for 6 to 7 minutes turning regular Slice the baps in half through the centre Butter the inside Add some lettuce leaves to the bottom layer Place 2 or 3 sausages in centre Top with a spoonful of the tomato relish Finish with the top of the bap and enjoy!