Wash your mushrooms, scoop out the stems and place them in a bowl. Put your mushrooms caps in the marinade and let them sit while you make the stuffing.
Chop the nuts in your food proccesor or blender. Add in the mushroom stems, onion, garlic and celery. Pulse until blended but still has some chunkiness to it. Mix in the dill and add a bit of your marinade to make it hold together better (you could also use water if you don’t want it too salty).
Scoop a heaping spoonful into your mushroom caps and voila! You could dehydrate them if you wanted to eat them warm.