Preheat the oven to 350°F/180°C. In a large roasting pan, combine the mushrooms with 1 tablespoon of the oil and 1½ teaspoons of the salt and toss to coat all over. Roast for 10-15 minutes until cooked through.
Take a large bowl and mix together the vinegar, garlic, parsley, marjoram, paprika, brown sugar, onion powder, garlic powder, lemon zest, pepper, and the remaining salt . Add the warm mushrooms and toss through to coat evenly. Cover and place in the fridge for about 2 hours before serving. This will give time for the mushrooms to take on all those yummy flavours.
