In a small bowl, combine mayonnaise, oil, dill and parsley. Set aside.
Prepare 4 pieces of large parchment paper folded then opened up in conveyor style.
Pat dry fish fillets and generously slather them with the mayo/oil mixture. Place them on one half of the parchment paper.
Layer veggies in the order given above. Salt and pepper to taste.
Fold the other half of the parchment paper on top of the fish and veggies and begin tightly crimping the edges together starting at one end and moving towards to other one, creating a half-moon. It helps to use one hand to firmly hold the contents of the packet as I make my way across the half moon shape.
Make sure the packet is tightly sealed. Place all packets on a rimmed baking sheet.
Bake the packets for 15 minutes or until fish is cooked through.
Use a pair of kitchen shears to cut the packet open. Be careful - it's hot and steamy.
Enjoy with a side salad or on it's own if it's loaded with veggies.