Clean the dock and chop it finely. Heat the oil in a pot on the stove and put the rosemary sprig to fry briefly. Pull it out and put the finely chopped onion in the oil. Once slightly softened, add the cleaned and sliced mushrooms, and garlic (crushed).
Allow to cook on a medium stove until the mushrooms soften. Add the rice, stir, and top up with 1 cup of water or broth. As soon as the liquid is absorbed, add 1 more cup, then another.
When the rice is ready, add spices to taste, the walnuts and chopped dock. Mix until the dock shrinks and remove it from the heat.
Distribute the dock with rice and mushrooms in glasses or dessert bowls. Serve turned over on a plate.