Toast hemp seeds or other nut/seed on a hot frying pan for about 1 minute, or until golden brown (but not burned). Remove from heat.
Bring large pot of water to boil.
Set aside large bowl of ice water.
Once water boils, place nettle into boiling water using tongs. If using fresh nettle, be careful not to touch with bare hands!
Blanch nettle for 1 to 2 minutes. This will remove the sting.
Remove nettle from boiling water and place in bowl of ice water to retain its bright, green color.
Turn off heat on boiling water, but reserve the water for boiling your pasta, if using the pesto as a pasta sauce. It can also make for a nutritious tea.
Once nettle has cooled (about 5 minutes), remove nettle by the handful and squeeze out water.
Place squeezed nettle on a kitchen towel to dry.
Combine nettle and remaining ingredients (except olive oil) in a food processor or blender.
Blend until ingredients are well mixed and form a paste.
With the blender or food processor running, slowly pour in oil until desired consistency is reached.
Your pesto is now complete! Use immediately, refrigerate, or freeze.