In a blender, blend the soaked cashews, water, lemon juice, apple cider vinegar, salt, mustard, nutritional yeast and a tiny pinch of turmeric together. If you don’t like the taste of turmeric you can leave it out but the sauce won’t be as yellow – and just add a tiny bit if you’re adding turmeric! You want a pale yellow sauce not fluorescent yellow 😛 Blend all the ingredients together until VERY smooth. I blend for one whole minute.
In a saucepan over low-medium heat, melt the vegan butter. Add the white wine and let cook for about 30 seconds-1 min so the alcohol evaporates.
Have a whisk handy! Pour the blended mixture into the pan and whisk immediately – the sauce will burn and may get lumpy if you don’t whisk. Whisk until the sauce thickens and is smooth! You can add a little water if it starts to get to thick until you reach your desired consistency!
Pour into a pouring jug and serve immediately! If it separates, simply mix well.