Pierce 1 small spaghetti squash (2½ pounds) all over.
On plate, microwave squash on High for 14 minutes or until tender; let cool.
Cut squash in half lengthwise; discard seeds.
With fork, scrape squash lengthwise; place strands in medium bowl.
Pit and chop ¼ cup Kalamata olives; add to bowl along with 3 tablespoons freshly grated Pecorino-Romano, 2 tablespoons chopped fresh parsley, 1 tablespoon olive oil, and 2 teaspoons red wine vinegar.