How to Make It
Preheat the oven to 350°. Spread the walnuts in a pie plate and toast for about 12 minutes, until golden. Let cool, then coarsely chop the walnuts.
Roast the peppers over a gas flame or under a broiler until blackened all over. Transfer to a bowl, cover and let cool. Peel and seed the peppers, then cut into very thin strips.
In a very large, deep skillet, heat the 6 tablespoons of olive oil. Add the garlic and cook over moderate heat, stirring, until fragrant, 30 seconds. Add the peppers, tomatoes, cumin and paprika and cook until the tomatoes are softened and just beginning to break down, 3 minutes. Add the orange juice and molasses and bring to a boil. Add the clams, cover and cook over high heat, shaking the pan occasionally, until the shells have opened, 6 minutes. Discard any unopened clams.
Meanwhile, in a large pot of boiling salted water, cook the bucatini until al dente. Drain the pasta and reserve 1/2 cup of the water. Return the pasta to the pot. Pour the clams, vegetables and sauce over the pasta and cook, stirring, for 1 minute; add some of the reserved pasta water if it seems dry. Add the chopped herbs and walnuts, season lightly with salt and toss gently. Transfer the pasta to wide bowls, drizzle with olive oil andserve.