1 tablespoon extra virgin olive oil
1 teaspoon butter
2 medium yellow onions, chopped (about 2 cups)
1/2 cup dry white wine (optional)
3 large Yukon Gold potatoes (about 1 1/4 pounds), peeled, cut into 3/4-inch cubes
2 cups clam juice or Seafood broth
1 bay leaf
1 tablespoon fresh thyme, or 1 teaspoon dried thyme
1 1/2 teaspoon salt
1/4 teaspoon freshly ground black pepper
1 teaspoon Old Bay (optional, can use a little paprika and a dash of cayenne)
1 1/2 to 2 pounds cod*, or other firm white fish, pin bones removed, fillets cut into 2-inch pieces
1 1/2 cups heavy cream
2 tablespoons chopped fresh parsley
1 Sauté onions in oil and butter, add wine: Heat oil and butter in the bottom of a large pot (6-qt) on medium heat. Add the onions and cook until softened, about 5 minutes.
Add the wine, if using, and turn up the heat, cook, uncovered until the wine reduces by half. (If not using wine, add a 1/4 cup of water with the clam juice in the next step.)
2 Add the potatoes, clam juice or seafood broth, bay leaf, thyme, pepper, and Old Bay spice. Do not add salt if you are using seafood or fish broth as they will have salt in them all ready. (The potatoes should be just barely covered with the liquid in the pot. If not, add water so that they are.)
Bring to a simmer, then lower the heat to medium and cook, covered, until the potatoes are almost done, about 10-15 minutes. Then add fish chunks and simmer an additional 5 minutes until the fish is cooked through.
3 Heat cream in a separate pot until steamy (not boiling)
NOTE: I use fat free half and half for a heathier version
4 Add heated cream to pot of potatoes and fish.
Keep your eye on the heat! If you are using straight heavy cream you should be more easily able to avoid curdling, even if the soup starts to boil. But if you are substituting light cream, half and half, or milk, the mixture will likely curdle if it gets near boiling point (one of the reasons I like using straight heavy cream).
Keep the temperature so that it barely gets steamy, but not simmering.