Preheat the oven to 375°F (190°C).
Slice the top off each bread bowl and scoop out the insides, leaving about half an inch of bread to create a sturdy shell. Set aside the bread for later use.
In a large pot, heat olive oil over medium heat. Add the chopped onion and sauté until translucent, about 5 minutes.
Stir in the garlic, celery, and carrots. Cook for an additional 5 minutes until the vegetables begin to soften.
Add the mixed seafood and sauté for 3–4 minutes until the seafood is opaque.
Pour in the seafood stock and bring to a simmer. Let it cook for about 10 minutes.
Reduce heat to low and stir in the heavy cream and Old Bay seasoning. Season with salt and pepper to taste. Allow the soup to warm through for another 5 minutes.
Ladle the seafood soup into the prepared bread bowls.
Place the filled bread bowls on a baking sheet and bake in the preheated oven for about 10 minutes until the bread is crusty.
Remove from the oven and garnish with fresh parsley before serving.