Rosemary Mushroom Burger & Fries

While the fries are baking, pick and finely chop the rosemary leaves. In a small bowl, combine the rosemary, the salt and a good drizzle of olive oil. Set aside. Thinly slice the tomato and brown onion. Shred the cos lettuce (see ingredients). Finely chop the garlic.

Heat a large frying pan over a medium-high heat. Remove the stems from the portabello mushrooms, then brush the mushrooms all over with the rosemary oil. Cook the mushrooms, turning occasionally, until softened and most of the water has evaporated, 15 minutes. Transfer to a plate lined with paper towel. TIP: Gently press down on the mushrooms with the back of a spatula to squeeze out excess water.

While the mushrooms are cooking, place the grated Parmesan cheese in even circular piles (about the same size as your buns) on a second oven tray lined with baking paper. Bake until the cheese is golden and crisp at the edges, 8-10 minutes. Remove from the oven and set aside. TIP: The Parmesan crisps will become crisp as they cool. TIP: Keep an eye on the cheese crisps, they can burn quickly!

Return the frying pan to a medium-high heat with the butter and a drizzle of olive oil. Add the onion and cook, stirring, until softened, 6-7 minutes. Add the garlic and cook until fragrant, 1 minute. Season with salt and pepper. Place the burger buns directly on a wire rack in the oven and bake until heated through, 3 minutes.