- 1/4 cup olive oil
- 2 1/2 cups chopped leeks (white and pale green parts only; about 2 large)
- 2 large bunches broccoli rabe (rapini), stemmed, coarsely chopped
- 4 garlic cloves, peeled
- 3/4 cup vegetable broth
- 1/3 cup crme frache or whipping cream
- 1 tablespoon finely grated lemon peel
- 1 cup grated Pecorino Romano cheese, divided
- 1 pound penne
- 1 1/2 cups walnut halves, toasted
- Heat oil in heavy large skillet over medium-high heat. Add leeks and sauté until golden and soft, about 5 minutes. Add broccoli rabe and sauté, tossing with tongs, until slightly softened and bright green, about 3 minutes. Add garlic and stir 1 minute. Stir in broth, crme frache, and lemon peel, then 1/3 cup cheese.
- Season to taste with salt and pepper. Meanwhile, cook pasta in large pot of boiling salted water until just tender but still firm to bite, stirring occasionally. Drain, reserving 1 cup pasta cooking liquid. Return pasta to pot. Stir in broccoli rabe mixture and walnuts, adding 1/2 cup cooking liquid to moisten and adding more by tablespoonfuls if needed. Divide pasta among bowls. Serve, passing remaining cheese separately.
- An Italian leafy green vegetable with scattered clusters of tiny, broccoli-like florets; available at some supermarkets and at specialty foods stores.