Instructions are for 4 servings. Please modify as needed.
Preheat the oven to 400°F (200°C).
Cut large pieces of parchment paper, one for each serving. Divide the green beans and fennel between them and place the fish on top. Season with salt and pepper, then top with the butter, garlic, thyme, lemon slices, and parsley.
Fold the parchment over the fish and vegetables and tightly crimp the edges to create sealed parcels. Place them on a baking sheet.
Bake for 12–15 minutes, depending on the thickness of the fish, until it is opaque and flakes easily with a fork and the vegetables are tender.
Meanwhile, mix the mayonnaise, garlic, and lemon juice in a small bowl to make the aioli.
Carefully open the parcels, allowing the hot steam to escape. Spoon the buttery juices over the fish and vegetables and serve with the lemon garlic aioli.
Can I use olive oil instead of butter?
Yes. Replace the butter with olive oil for a slightly lighter flavor. Butter gives the dish a richer taste and creates a delicious sauce with the juices released by the fish and vegetables.
Can I use other vegetables?
Yes. Replace the green beans with sugar snap peas, broccoli, asparagus, or zucchini. Keep in mind that cooking times may vary depending on the vegetable.
Can I use another type of fish?
Yes. Cod, haddock, pollock, or halibut also work well. Adjust the cooking time depending on the thickness of the fillets.