Shellfish with Fennel, Escarole, and Kale

In a small saucepan, heat the butter over medium heat until it turns golden-brown, 2 to 3 minutes. Pour into a small bowl and set aside.

In a 12-inch skillet, heat the olive oil over medium-high heat. Add the tomatoes and cook until they start to blister, 2 to 3 minutes. Add the fennel and garlic. Cook, shaking the pan, until the garlic becomes golden-brown, 2 to 3 minutes. Add the escarole and stir for 1 minute. Add the sherry, raise the heat to high, and cook until it evaporates, about 30 seconds. Add the fish broth and boil until it reduces slightly, 3 to 4 minutes. Add the clams, cover, and cook for 2 minutes. Add the mussels, cover, and cook for 2 minutes. Add the shrimp, cover, and cook for 1 minute. With a slotted spoon, transfer the open shellfish and shrimp to a large bowl and cover loosely with foil. Toss any that do not open.

Stir the kale and pepper flakes into the broth and cook until the kale wilts, about 1 minute. Remove from the heat and add the parsley and rosemary. Pour in the browned butter. Add the lemon zest and juice. Season to taste with salt and pepper.

Distribute the broth, vegetables, and seafood among 4 wide, deep bowls. Garnish with parsley.