Combine The Cooked Brown Rice, Milk, Blueberries, Cinnamon, And Honey In A Small Saucepan. Bring To A Boil, Then Reduce Heat To Low And Simmer For 20 Minutes. Beat The Egg In A Small Bowl. Temper The Egg By Whisking In Some Of The Hot Rice, A Tablespoon At A Time Until You Have Incorporated About 6 Tablespoons. Stir The Egg Into The Rice Along With The Vanilla And Butter, And Continue Cooking Over Low Heat For 1 To 2 Minutes To Thicken.