1Preheat oven to 350F.
To prepare filling, combine first 4 ingredients in an 11x7-inch baking dish.
To prepare topping, lightly spoon four into dry measuring cups; level with a knife.
2Combine flour and next 4 ingredients(flour through baking soda) in a large bowl, stirring with a whisk. Cut in the butter or margaine with pastry blender or 2 knives until mixture resebles coarse meal. Stir in sour cream to form a soft dough.
3Drop dough by spoonfuls onto blueberry filling to form 8 dumplings. Brush dumplings with milk; sprinkle with 1 teaspoon sugar. Place baking dish on a jelly roll pan. bake at 350F for 50 minutes or until filling is bubbly and dumplings are lightly browned.