You can use roasted or raw hazelnuts for this, but if you roast them, make sure to do it yourself (for 10 minutes on a stovetop over low heat). Smaller seeds will need to be roasted for more like 3-5 minutes. Then soak your nuts or seeds 8+ hours or overnight.

Drain off the water you soaked the nuts in, rinsing off any excess soaking water. Then put your nuts in a high-powered blender with 3 cups of fresh filtered water and your sweetener (if using).

Blend everything for about 2 minutes, mixing it in long pulses of 10-15 seconds until completely blended.

Line a large bowl with nut milk cloth or a very old 100% cotton piece of clothing, like an old white t-shirt, and then strain everything, squeezing all the excess milk form the cloth. Your milk is now all done and can be refrigerated for up to 5 days, but you'll be left with a lot of nut milk pulp. To deal with that, turn it into the nut meal described below, which can be used in a variety of other recipes.

Spread out the nut milk pulp in the oven at 170°F (75°C) for 60-75 minutes to turn it into a high-protein nut meal you can use in recipes like my no-bake protein balls.