Preheat your oven to 375°F (190°C). If using individual ramekins, grease them lightly.

In a wide skillet over medium heat, melt the butter with olive oil. Add the finely chopped onion and sauté until soft and fragrant, about 2–3 minutes. Stir in the minced garlic and cook for another 30 seconds.

Gently add the seafood mix to the skillet. Cook just until the seafood starts to become opaque. Transfer the seafood to a plate using a slotted spoon, leaving behind the buttery juices.

Into the same pan, pour in your broth and let it simmer gently, scraping up any flavorful bits stuck to the bottom. Stir in the heavy cream and simmer for about 5 minutes until slightly thickened.

Add the Parmesan cheese gradually, stirring until melted into a silky sauce. Add lemon zest, salt, and pepper to taste.

Place the seafood back into the sauce and mix gently to combine. Spoon the mixture into ramekins or a single medium baking dish. Sprinkle the panko breadcrumbs evenly over the top, followed by a light dusting of Parmesan.

Place the ramekins or dish in the oven and bake for 15–20 minutes, or until the top is golden and the sauce is bubbling around the edges.

Remove from the oven and sprinkle with chopped parsley or dill. Add lemon wedges on the side. Serve immediately while piping hot.