These delicate custards are a great way to showcase the subtle, nutty flavor of homemade nut milk. Slideshow: More Panna Cotta Recipes
In a small bowl, sprinkle the gelatin over 1/2 cup of the nut milk and let stand until softened, about 5 minutes. In a medium saucepan, combine the remaining 2 1/2 cups of nut milk with the sugar, honey, vanilla seeds and salt. Bring just to a simmer over moderately high heat. Remove the pan from the heat and whisk in the softened gelatin mixture until dissolved.
Lightly brush six 1/2-cup ramekins with oil and set them on a baking sheet. Carefully fill the ramekins with the panna cotta mixture and refrigerate until set, about 2 hours and up to 2 days.
Run a knife around each panna cotta and invert onto a plate. Top with crushed hazelnuts and serve with the jam.
The gelatin prevents it from being vegan, which the nut milk seems to imply the benefit is. Agar-agar should be listed as a substitute.