Preheat oven to 400°F.
In a large bowl, measure flour, sugar, baking powder, salt and cinnamon.
Grate cold butter using a grater or cut cold butter into flour mixture with either a pastry blender, a fork or your fingers to break the butter into small pea-size pieces.
Measure and whisk milk/cream, egg, vanilla and lemon juice into a measuring cup or small bowl. Then slowly add the wet ingredients into the flour mixture, until no flour is visible. Gently fold in blueberries. The dough should be moist.
Using your hands, gently press dough onto floured surface shaping into a circle to about one inch thickness. If the dough is too stick, add additional flour. Using a chef’s knife, cut the circle into 8 equal slices.
Carefully separate slices, and place on a baking sheet lined with parchment paper. Bake for 25-30 minutes, or until golden in colour. Cool on a cooling rack before serving.
Lemon Glaze: Using a wire whisk, beat together the powdered sugar, milk, and lemon. Drizzle over scones and serve.