1: Whack the oven on at 180C.

2: Drizzle the vegetable oil onto a baking tray or roasting tin. Pop on the sausages and cook them in the hot oven for 25 minutes, or according to the packet instructions, turning a couple of times to make sure they cook all the way through and are evenly browned. 

3: Meanwhile, peel the sweet potato and cut it into chunks. Bring a pan of water to the boil and add the sweet potato, cooking for 10-12 minutes until soft. Drain the sweet potato and then return it to the pan and warm through over a low heat to draw out any excess moisture. Mash the sweet potato with a fork or masher, then set aside. 

4: For the gravy, peel and slice the onion, then heat the vegetable oil in a frying pan over a medium heat. Once hot, add the onion and fry for 8-10 minutes until softened and turning golden brown. Crumble in the stock cube and add the flour, then stir it all together and cook for 1 minute. 

5: Add the mug of water and bring it to the boil so it’s bubbling, and continue to stir until thickened. Add in the brown sauce (if using) and vinegar, give it another stir, and keep it bubbling gently until ready to serve. 

6: Put the frozen peas in a bowl, then cover with a plate and microwave on full power for 2½ minutes.

7: To serve, pop the sausages on plates and spoon the sweet potato mash and peas alongside. Pour over the gravy, and tuck in!