Portobello Mushroom Burger With Walnut Pesto

Preheat the oven to 220°C/ 200°C (fan)/ gas 7

Chop the potatoes (skins on) into bite-sized pieces

Add the chopped potatoes to a baking tray with a generous drizzle of olive oil and season generously with salt and pepper

Give everything a good mix up and put the tray in the oven for an initial 25 min or until golden

Meanwhile, peel and finely slice the red onion[s]

Cut 4 [8] thin slices from the tomato[es] and set them aside for serving

Finely dice the remaining tomato

Chop the basil coarsely, including the stalks

Peel and finely chop (or grate) the garlic

Add the portobello mushrooms to a separate baking tray with the dried oregano, a generous drizzle of olive oil and a pinch of salt and pepper

Put the tray in the oven for an initial 15-20 min or until softened

Once softened, add half of the grated Italian hard cheese

Return the tray to the oven for a further 4-5 min or until the cheese has melted – these are your cheesy portobello mushrooms

While the mushrooms are cooking, heat a large, wide-based pan (preferably non-stick) with a drizzle of olive oil over a medium heat

Once hot, add the walnuts and toast for 2-3 min or until lightly toasted

Once lightly toasted, add the chopped garlic and cook for a further 1-2 min or until fragrant

Once fragrant, transfer the toasted walnuts and garlic to a food processor, set aside and reserve the pan for later

Return the reserved pan to a medium heat with a drizzle of olive oil

Once hot, add the sliced onion with the balsamic vinegar, 2 tsp [4 tsp] sugar and a pinch of salt and cook for 6-7 min or until softened and caramelised

Meanwhile, add the chopped basil to the food processor with half of the grated Italian hard cheese, 2 tbsp [4 tbsp] olive oil and a pinch of salt and pepper and blitz together – this is your walnut pesto

Cut the ciabattas in half

Once the potatoes are golden, remove the tray from the oven, push them to one side of the tray and add the ciabattas to the other side

Return the tray to the oven for a further 3 min or until the ciabattas are warmed through

Combine the mayo and half of the walnut pesto in a small bowl with a grind of pepper – this is your pesto mayo

Wash the baby leaf salad, then pat it dry with kitchen paper

Add the remaining walnut pesto to a large bowl with 1 tbsp [2 tbsp] water and mix to combine

Add the washed salad and diced tomato and give everything a good mix up – this is your tomato salad