Method

1. Heat oven to 220°C. In bowl, mix the flour and mustard powder with some salt. Make a well in the centre, crack in the egg and pour in a bit of milk. Stir, gradually incorporating the flour, until a smooth batter in the well. Add a bit more milk and continue stirring until all the milk and flour has been mixed together and you have a smooth batter.
2. Place sausages in a roasting tin. Add 1 tbsp oil and toss the sausages. Roast in the oven for 15 mins.
3. Take hot tray from oven and pour in the batter. Place cherry tomatoes over the batter and place back into oven. Bake for 40 minutes until the batter is cooked through, well risen and crisp.
4. Make the gravy: Fry the onions until they are golden brown. Sprinkle in the sugar. Add flour and stir for 2 mins. Gradually pour in the stock, stirring well to make a smooth sauce. Bubble for 4-5 minutes to thicken, then season. Cut the toad in the hole into large wedges and serve with the gravy spooned over.