Using a vegetable peeler, peel off two large strips of lemon zest.
Bring orzo, broth, oregano and lemon zest to a boil. Reduce heat to a simmer and cook 13-15 minutes uncovered or until the orzo is tender.
Remove from heat and remove and discard the lemon peel. Stir in butter and let the orzo rest uncovered for 5 minutes.
Juice half of the lemon over the orzo, add mint or parsley and stir. Season with salt & pepper to taste.