To make the batter

1. In a bowl, whisk together all the ingredients except the salt until well combined.
2. Cover and refrigerate overnight to rest. The next day, add the salt and whisk again until smooth.

To make the Toad in The Hole

1. Preheat the oven to 180°C (fan).
2. Bring a large pan of water to a boil — big enough to comfortably fit the sausage spiral.
3. Once boiling, carefully add the sausage and poach for 10 minutes, ensuring the spiral is open so it cooks evenly. Remove the sausage and place it on a rack to cool.
4. Set a medium frying pan (20–25 cm) over a medium heat.
5. Add the oil and fry the sausage on both sides until golden brown.
6. Remove the sausage from the pan and set aside. Clean the frying pan and add a dash of oil.
7. Pour in a layer of batter, about 1 cm deep into the pan, and cook for 30 seconds until it begins to set.
8. Remove the pan from the heat.
9. Return the sausage to the pan, opening up the coil to leave gaps for the fillings.
10. Fill the gaps between the sausage with the remaining ingredients, making sure they sit neatly and don’t stick out above the batter.
11. Place the pan back over a high heat.
12. Pour over the remaining batter to cover the sausage and fillings.
13. Cook for 1 minute, or until the batter starts to set around the edges.
14. Transfer to the oven and bake for 25 minutes, or until the batter is puffed up, golden, and fully cooked.
15. Allow to rest for 5 minutes.
16. Turn the Toad in the Hole out onto a chopping board and slice into wedges.

To make the sauce

1. In a medium saucepan, melt the butter and gently sweat the diced onion until softened.
2. Add the bacon and cook for a further 5 minutes until lightly browned.
3. Pour in the gravy and bring to a gentle simmer.
4. Stir in the remaining ingredients.
5. Taste and adjust the seasoning with salt, pepper, and a splash of vinegar as needed.