Instructions

  1. Heat oil in a Dutch oven over medium-high heat.
  2. Add in chopped onion, garlic, oregano and crushed red pepper flakes; saute for about 5-6 minutes.
  3. Add in tomatoes with juice and drained mushrooms along with black and green olives; simmer on low heat for about 25-30 minutes, or until mixture starts to thicken.
  4. Add in cooked pasta shells and 3/4 - 1 cup grated Parmesan cheese; toss to combine.
  5. Serve with more Parmesan cheese.