Preheat oven to 350F
Spread the blueberries out over the bottom of a baking dish (mine was about 10x10") and sprinkle 3/4 cup of the sugar over the berries.
In a medium bowl, beat the butter, oil and remaining 1/2 cup sugar until creamy; add the egg and beat until smooth. In a small bowl, stir together the flour, baking powder and salt.
Add half the dry ingredients to the butter mixture, beating on low speed just until blended. Beat or stir in the milk, and then add the remaining flour, beating or stirring just until combined. It should have the consistency of thick cake batter. Drop in large spoonfuls over the berries - I did mine in three rows of three. If you like, sprinkle with coarse sugar.
Bake for 40-45 minutes, until the berries are bubbly and the dumplings are golden and cooked through. Serve warm. Serves 9.