Preheat oven to 425°. Prepare 1 baking sheet or 2 cake pans with parchment paper.
Combine all dry ingredients in bowl and mix together.
Cut in butter until in small crumbles.
Shred apple. Squeeze out excess juice. Add to mixture.
Mix together buttermilk and egg. Add to mixture.
Bring everything to a dough. If dough is sticky, add a little flour.
Turn out onto floured surface. Knead a few times.
Form into two 6-inch rounds. Place on prepared baking sheet or in prepared cake pans. Score the rounds into 6 scones. Sprinkle with cinnamon and sugar.
Bake in oven for 15-20 minutes or until golden brown. Remove and cool.
When scones are cooled, whisk together glaze ingredients and drizzle over scones. Let glaze harden before serving or storing.