This easy recipe is an alternative to the chickpea water (aquafaba) based recipes that are common with vegan deserts. My Little is anaphylactic to chickpeas, lentils, and round legumes but can safely eat white beans, kidney beans, and black beans. It's been my experience that white kidney bean water is a close substitute and works just as well.
Brine from one can of white kidney beans
1 cup of powdered sugar
1 tsp vanilla
1/2 tsp almond extract (optional)
Whip bean brine at high speed until soft peaks appear (this takes longer than with egg whites so be patient).
Continuing at high speed, slowly add sugar and vanilla/almond extract
If you're using this for an icing base or topping, you can fold it into whatever you are making (I use it for vegan amaretti cookies at Christmas time, so yum). You can also pipe and bake it for marshmallowy, crunchy cookies. Bake them on parchment paper at 200F for about 2 hours.