Soak the cashews in boiling water for 20 minutes or in cold water overnight.
Thinly slice the brown onions.
Heat up a fry pan and add the sunflower oil. Add the sliced onions and cook for 15 minutes on low-medium heat until caramelised. Stir occasionally and add a splash of water at the 7 minute mark.
Once the onions are caramelised, add 3/4 of the onions to a high-powered blender.
Drain the cashews and add them to the blender along with the leaves from one rosemary sprig, soy milk, miso, salt and white wine vinegar.
Blend everything until smooth and creamy. Add more soy milk if a thinker consistency is desired.
To serve, add the dip into a bowl and top with the leftover caramelised onions, chopped rosemary and cracked black pepper. Enjoy!