To make scones with Bisquick, combine the baking mix with sugar, butter, berries, eggs and milk, and bake the mixture for 15 minutes at 450 degrees Fahrenheit. Glaze the scones with lemon glaze before serving.
Preheat the oven to 450 degrees Fahrenheit, and mix 2 1/2 cups Bisquick with 1/4 cup sugar. Cut 1/4 cup unsalted butter into the mixture until the butter forms pea-size pieces. In a separate bowl, beat 2 eggs and 1/4 cup milk together, and combine the eggs and milk with the dry ingredients. Mix to form a dough. Fold 1/2 cup blueberries into the dough if desired, and place the dough on a floured surface.
Roll the dough to 3/4-inch thickness, cut the dough into four squares, and cut each square into two triangles. Place the triangles on a baking sheet, and bake the scones for 15 minutes at 450 F. To make a glaze for the scones, mix 1 cup powdered sugar, 1/2 teaspoon vanilla extract and the juice from 1 lemon. Blend the glaze until it is smooth, and pour it over the warm scones before serving. Other fruits and nuts, such as dried cranberries and walnuts, can be substituted for the blueberries.