Cheesy Veggie Burger and Crispy Onions

While the wedges cook, halve the burger buns, halve, peel and thinly slice the onion. Grate the Cheddar cheese. Pop half the Dijon mustard in a salad bowl and add the olive oil (see ingredients for amount). Season with salt, pepper and a pinch of sugar. Mix together and pop to one side. Put the remaining Dijon mustard in a small bowl, add the mayonnaise and mix together. Set aside.

Meanwhile, put enough oil in a large frying pan to cover the bottom, then pop on medium heat. Put the flour into a bowl and season with salt and pepper. Separate the onion slices, add them to the flour and toss to coat. When the oil is hot, add the onion and fry in batches until golden and crispy, 2-4 mins. Turn once or twice, then transfer to some kitchen paper to absorb any excess oil. TIP: To check whether the the oil is hot enough, put one onion slice into the pan - if it sizzles, it's ready.

Once the onions are out of the pan, discard some of the oil - you want roughly 1 tbsp left in the pan. Pop the pan back on high heat. Lay in the veggie burgers and fry them until nicely browned, 3-4 mins each side. Once browned, remove the pan from the heat. Carefully place the cheese on top of the burgers. Cover with a lid or some tin foil and set aside off the heat, for 3-4 mins so the cheese melts.

Meanwhile, pop the burger buns on a baking tray and place on the middle shelf of your oven. Warm for the last 3-4 mins of the wedge cooking time. Add three-quarters of the rocket to the dressing and toss to coat.