Preheat the oven to 425ºF. Line a baking sheet with parchment paper. Set aside.
Combine the flour, sugar, baking powder and salt in a large bowl. Cut the butter into small pieces. Add the butter to the flour mixture then cut it in using two knives until the mixture resembles coarse meal. (This step may also be done in a food processor fitted with a metal blade.)
Combine the egg and cream in a small bowl and beat well. Add the liquid to the flour mixture. Stir with a wooden spoon until a soft dough is formed. Scrape the dough onto a lightly floured surface. Knead the dough a few times just until it comes together.
Divide the dough into two even pieces. Roll each piece into a ball. Flatten each ball of dough with a lightly floured rolling pin into a circle about 8-inches in diameter. Spread the Cinnamon Schmear over one disc of dough. Place the second piece of dough on top. Pinch the edges to seal the two pieces of dough together.
Cut the dough into 8 or 12 pie-shaped wedges using a long kitchen knife or rolling cutter. Position each piece of dough on the prepared baking sheet spaced a few inches apart. Brush the tops with milk or water.
Bake the scones until lightly browned on top and slightly puffed, about 12 to 15 minutes.
Let the scones cool on a wire rack for 10 minutes.
Combine the powdered sugar and lemon juice in a small bowl. Drizzle the tops of the baked scones with the sugar glaze using a teaspoon or fork.