Ingredients
Instructions
- Preheat the oven to 400 F or 200 degrees C.
- Place onions, rosemary and a bit of salt in a small saucepan and cover with 1 cup water.
- Bring to a boil, then turn down the heat immediately.
- Cover and cook, stirring once or twice, for about 15 minutes until the onions are very soft, uncoloured and most of the liquid has disappeared.
- Meanwhile, peel the potatoes and cut into chunks.
- Rinse and boil in lots of salted water.
- Also, smear the sausages with oil, then place in a casserole dish and cook in the oven for about 30 minutes, turning half way through.
- Finish the onion sauce by boiling hard if necessary to get rid of any extra water.
- Discard the rosemary stalk, sift the flour over the top and stir.
- Add the mustard and 1 cup of the milk.
- Simmer gently for at least five minutes to cook the flour and make a thick, creamy sauce.
- Make the mash by draining the potatoes, adding the remaining milk and butter and mashing until smooth.
- Whip with a wooden spoon to make the mash light and fluffy, adding extra butter or milk if it's too thick.
- Divide onto plates, top with the sausages and a generous spoonful of gravy.