Preheat the oven to gas 8, 230ºC, fan 210ºC. To make the batter, put the flour, eggs and milk in a small blender with a pinch of salt and pepper and whizz until smooth.
Heat 2 tablespoons of the oil in a 4-hole Yorkshire pudding tin on the hob and briefly brown the chipolatas, two in each hole. Pour the batter into the hot tin, around the chipolatas, and top each hole with a sage leaf. Cook in the oven for 15-20 minutes.
Meanwhile, make the gravy. Heat the remaining 1 tablespoon of oil in a large frying pan and cook the onion for about 5 minutes until softened and golden brown. Stir in the flour, cook for 1 minute, then add the cider. Stir well, scraping up all the flour. Add both mustards and bring to the boil, and cook for a further 5 minutes until thickened. Season. Serve with the toad in the holes and some peas, if you like.
For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.