Either fry the nettles quickly (about 30 seconds) or add them to a pot of boiling water for 1 minute (to remove any irritating hairs). If you use the latter method, make sure you strain your nettle well
Chop and mix dandelion leaves and nettles (using a mortar or blender) with olive oil
Add the garlic cloves and salt. Keep crushing until everything is rather smooth
Taste, and then season to your taste. If it’s too thick, you can thin it with more olive oil or with lemon juice
Notes
Optional: add pepper, aromatics, cheese and pine nuts to your sauce.