Toss the mushrooms in the tamari, olive oil and lemon juice for a few minutes.
Dehydrate in for 3 hours at 115 degrees F, or if using an oven, place on a baking tray and cook on the lowest temperature, which is usually around 150 F (65 C) for about an hour, keeping an eye on them, so they’re lightly cooked and softened.
Pulse the rocket leaves, walnuts, nutritional yeast, lemon juice, garlic and salt in a food processor.
Whilst the food processor is running pour in the olive oil so it emulsifies and doesn’t separate later on.
Serve a couple of spoonfuls on each of the warm mushrooms straight out of the dehydrator or oven.