Preheat oven to 375 degrees F (190 degrees C). Roll out crescent dough triangles onto a baking sheet.
Place 1 tablespoon blueberries on the widest end of each triangle. Sprinkle 1/2 teaspoon confectioners' sugar over blueberries on each roll. Beginning with the wide end, roll up each crescent around blueberries; pinch both sides to seal completely.
Bake in the preheated oven until golden, about 12 minutes. Remove to cool on a wire rack for 5 minutes; dust with the remaining confectioners' sugar. Drizzle with the vanilla frosting.