Toast oatmeal in a saucepan over medium heat until lightly golden brown. Add walnuts and toast for 30 seconds more. Add blueberry juice, sugar, blueberries, and cinnamon stick and bring to a simmer. Reduce heat to medium-low, and simmer for 20 to 25 minutes. Remove from heat and allow sirup to cool for about 15 minutes. Strain through a fine mesh strainer.
Stir in butter extract, and a very small pinch of salt. Transfer into a smaller container, and store in the fridge until needed.
To make the dirty soda, fill a glass with ice, and pour in 2 ounces of cream soda. Fill the glass the rest of the way with berry sparkling water, or berry soda if you want something sweeter, leaving a half inch unfilled at the top. Pour in 3 to 4 tablespoons of the blueberry syrup, and stir everything with a spoon for a few seconds. Top of the splash of half and half, And a dollop of whipped cream if desired. Garnish with Grape Nuts cereal, or pinch of cinnamon.
