How to Make It
In a medium bowl, cover the hazelnuts, almonds, Brazil nuts and vanilla bean with filtered water and let stand overnight at room temperature.
Drain and rinse the nuts and vanilla bean; transfer to a blender. Add the honey, 5 cups of water and salt to the blender and puree on high speed until very smooth, about 2 minutes. Pour the nut milk through a cheesecloth-lined fine sieve set over a bowl and let drain for 30 minutes. Using a spatula, press on the solids to extract any remaining milk; discard the solids. Pour the nut milk into an airtight container and refrigerate until chilled, about 30 minutes. Stir or shake before serving.
You can use the leftover ground nuts in baked goods or smoothies. After making nut milk, spread the nuts out on a rimmed baking sheet in an even layer and bake at 200° until pale and dry, about 2 hours. Let cool completely, then pulse in a food processor until fine crumbs form.