How to Make It
Preheat oven to 450°.
Coat inside of oven bag with cooking spray. Place the bag on a large shallow baking pan.
Combine broth and next 11 ingredients (broth through tomatoes) in a large bowl, and stir in couscous. Place couscous mixture in prepared oven bag. Place tuna on couscous mixture. Fold edge of bag over to seal. Bake at 450° for 20 minutes or until fish is medium-rare or desired degree of doneness. Cut open the bag with a sharp knife, and peel back foil. Sprinkle with the toasted pine nuts and 1 tablespoon parsley.