Preparation Heat a deep 12-inch heavy skillet (not nonstick) over high heat until a bead of water dropped on cooking surface evaporates immediately. Add clams and fennel seeds, then cover skillet and cook, shaking skillet, until clam shells are lightly browned, 1 to 2 minutes. Add oil and toss to coat clams. Stir in scallions, garlic, and tomatoes, then sauté, stirring, until tomatoes begin to soften, 2 to 3 minutes. Add wine, water, Pernod, and red pepper flakes and bring to a boil. Cover and steam clams, shaking skillet occasionally, until they open, 7 to 10 minutes. (Discard any unopened ones.) While clams are steaming, cook linguine in a 6- to 8-quart pot of boiling salted water until al dente, then drain in a colander. Add linguine, butter, and parsley to clams and toss over low heat until pasta is coated with sauce. Season with salt and pepper and serve immediately.
Preparation Heat a deep 12-inch heavy skillet (not nonstick) over high heat until a bead of water dropped on cooking surface evaporates immediately. Add clams and fennel seeds, then cover skillet and cook, shaking skillet, until clam shells are lightly browned, 1 to 2 minutes. Add oil and toss to coat clams. Stir in scallions, garlic, and tomatoes, then sauté, stirring, until tomatoes begin to soften, 2 to 3 minutes. Add wine, water, Pernod, and red pepper flakes and bring to a boil. Cover and steam clams, shaking skillet occasionally, until they open, 7 to 10 minutes. (Discard any unopened ones.) While clams are steaming, cook linguine in a 6- to 8-quart pot of boiling salted water until al dente, then drain in a colander. Add linguine, butter, and parsley to clams and toss over low heat until pasta is coated with sauce. Season with salt and pepper and serve immediately.