Step 1
Cook pasta in a large saucepan of boiling, salted water, following packet directions. Drain pasta, reserving 1 cup cooking liquid.
Step 2
Melt butter in a large frying pan over medium-high heat. Add garlic and pepper. Cook, stirring, for 1 minute or until fragrant. Stir in reserved pasta water. Add parmesan and pecorino. Whisk to form a thin sauce. Add pasta. Toss to coat. Sprinkle with chives.