2 tsp un-refined brown sugar
First peel the potatoes and place in seasoned water and boil for approx 20 mins until knife tender, meanwhile, heat a non-stick pan, add a tsp of ooil and cook the sausages gently turning regular until cooked.
At the same time heat a pan, add the rest of the ooil and pan fry the sliced onions and pan fry gently for 15 minutes, add the sugar and caramalize for another 5 minutes. Add the water, a knob of butter and reduce to the consistency you require for your gravy, sometimes I add some chicken stock to deepen the flavour, season to taste.
Once the potatoes are ready, push them through a ricer for a smoother texture back in to a warm pan, add lots of butter and seasoning, I like to add some vinegar, this is what my nan always did and it adds a lovely taste to the mashed potatoe, well not that my dad agrees!