1. Bring 6 quarts water to a boil in a large pot; season with salt.
2. Meanwhile, in a 10- to 12-inch skillet, heat olive oil over medium heat until almost smoking. Add onion and red pepper flakes; saute until translucent, 8 to 10 minutes. Add jalapenos; saute for 1 minute. Add zest and juice; bring to a boil, and boil for 1 minute. Remove from heat; stir in butter, and season with salt and pepper. Set aside.
3. Drop pasta into boiling water and cook until tender, 1 to 2 minutes. Drain.
4. Toss hot pasta into pan with lemon mixture; return to medium heat. Stir together gently. Add pecorino; toss quickly. Transfer to a warmed serving platter. Serve immediately.
This recipe is adapted from Mario Batali's Molto Italiano. (Ecco, 2005).
Andrea Reusing is the creator of the restaurant Lantern in Chapel Hill, N.C., and author of the book Cooking in the Moment: A Year of Seasonal Recipes. In this installment of The Key 3, she shares with Lynne Rossetto Kasper the techniques behind three of her favorite recipes: Turnip Soup, Overnight Braised Short Ribs and Tomato Salad.