4 tablespoons unsalted butter (cut into 4 pieces and chilled)
Preheat oven to 375F.
In a medium bowl gently mix together the blueberries with the granulated sugar, cornstarch, and a pinch of salt. Divide blueberries between 2 – 12-ounce ramekins.
In another medium size bowl mix together the oats, flour, brown sugar, cinnamon, and a pinch of salt. Using your hands work the butter into the mixture until dime size clumps form; sprinkle the mixture over the top of the blueberries.
Place ramekins on a cookie sheet and bake until bubbly around the edges and topping is a deep golden brown.