In a large bowl, soak almonds and cashews in 4 cups (1 L) water for 8 hours. Drain nuts, then rinse with plenty of water.
In blender, purée almonds and cashews, 2 cups (500 mL) filtered water and honey until thick and creamy. Add yogurt (or culturand salt, then blend for a few seconds.
Pour into jars, leaving about 1 inch (2.5 cof space on top, and seal airtight. Place in a yogurt maker, dehydrator or any other incubator (for example, the oven of an electric range, with heat off but oven light oat 90°F to 104°F (32°C to 40°C). Let ferment for 6 to 8 hours.
Taste and, if needed, let ferment awhile longer for more pronounced flavor.
When yogurt is ready, shake jars to mix contents, then refrigerate.
For thicker yogurt, place a fine-mesh sieve over a bowl and line it with several layers of cheesecloth. Transfer yogurt to sieve and refrigerate for a few hours, until liquid has drained. Transfer yogurt to an airtight container.