Saute onion in olive oil until translucent; add tomato paste and saute for about 2 minutes.
Add remaining ingredients (except butter, red pepper flakes and Parmesan cheese).
PRESSURE COOKER / INSTANT POT METHOD: cook on "Rice" setting for 12 minutes; natural pressure release. REGULAR STOVETOP METHOD: cook for about 20 minutes or until rice is cooked through; add more broth or water if necessary.