Grating plum tomatoes for Catalan fish stew makes an instant puree. Cooking the tomato puree with serrano ham and olives adds layers of flavors to the stew. More Hearty Stews
Using a box grater set in a bowl, carefully grate the cut sides of the tomatoes, stopping when you reach the skin. You should have about 2 cups of tomato pulp.
In a large, deep skillet, heat 1 tablespoon of the olive oil. Add the onion and half of the garlic and cook over moderate heat, stirring frequently, until they are softened and just beginning to brown, about 6 minutes. Add the tomato pulp and cook over high heat until it is thickened, about 5 minutes. Add the clam broth and boil until it is reduced by half, about 5 minutes.
Add the serrano, olives and halibut and simmer over moderate heat, stirring occasionally, until the fish is cooked through and the stew is thick, about 5 minutes longer.
Meanwhile, in a small bowl, using the back of a spoon, mash the remaining garlic to a paste with a pinch of salt. Whisk in the mayonnaise, pimentón and the remaining 2 tablespoons of olive oil.
Serve the fish stew in shallow bowls with a dollop of the pimentón mayonnaise.
The smoked-paprika mayonnaise can be refrigerated for up to 2 days.
Albariño is Spain's best-known white, but there are others that belong on the table as well. One is Godello, a medium-bodied wine that has enough structure to go with this flavorful stew.