Preheat oven to 450F.
In a mixing bowl, combine mushrooms, olive oil, salt, and pepper; mix to combine.
Transfer mushrooms to a rimmed baking sheet and bake for 8 to 10 minutes, or until tender and browned.
In the meantime, prepare the sauce.
In a microwave safe cup or bowl, combine tomato sauce, onions, capers and lemon rind.
Microwave on high for 30 seconds or until thoroughly heated.
Remove mushrooms from oven and let stand a few minutes.
Toss the mushrooms with previously prepared sauce.
Garnish with parsley.
Recipe developed by: http://www.diethood.com
Prep Time: 10 mins
Cook Time: 10 mins
Total Time: 20 mins