- Pre heat the oven to 180 fan. Pop the kale into a mixing bowl and add 1 tbsp of the oil. Toss well. Add the Chinese 5 spice and a good pinch of salt and mix well. Transfer to a baking sheet and roast for 8-10 minutes until crispy. Set to one side.
- Heat the remaining oil in non-stick oven proof frying pan over a high heat. Add the mushrooms, stalk side down and cook for 3-4 minutes until really golden. Flip them over and pop the pan into the oven and cook for 6-8 minutes until tender. Remove from the oven.
- Pre-heat the grill to high. Turn the mushrooms over so any liquid comes out and add the hoisin sauce to the pan. Turn the mushrooms a few times in the sauce. Sit them stalk side up and fill the little cavities with the sauce. Pop under the grill for 3-4 minutes to caramelise. Carefully remove the pan from the grill and spoon the sticky juices over the mushrooms.
- Meanwhile, mix the mayonnaise with the sriracha and a pinch of salt.
- To serve, dollop plenty of mayonnaise onto the burger buns and top with the mushrooms and plenty of crispy kale. Serve immediately.
60g kale, picked
3 tbsp olive oil
1 tsp Chinese 5 spice
4 large portobello mushrooms
4 tbsp hoisin sauce
2 tbsp sriracha
4 brioche burger buns