
Place the bacon in a cold large stock pot over medium heat. Cook until the bacon is crisp and the fat is rendered, about 10 minutes, reducing the heat as necessary to avoid burning. Transfer the bacon to a paper towel-lined plate, reserving the drippings in the pot.
Return the pot to medium heat and add the onions, celery, carrots, salt, and pepper. Cook, stirring, until softened, about 5 minutes. Add the garlic and Old Bay and cook for 1 minute, until fragrant.
Add the wine and scrape up any browned bits on the bottom of the pot. Simmer until the wine is mostly evaporated, about 2 minutes.
Add the seafood stock, return the bacon to the pot, and bring to a boil. Add the potatoes. Allow to return to a simmer, then reduce the heat to low, and continue simmering uncovered until the potatoes are tender, about 5 minutes.
Add the shrimp, cod, scallops, and clams and their juices. Return the soup to a bare, gentle simmer for about 2 minutes, until the seafood is just cooked through. Add the half and half and remove the pot from the heat.
Adjust the seasoning to taste. Top with parsley or thyme to serve.