Preheat the oven to 450 degrees F (or 232 degrees C).

Line a baking sheet with a piece of parchment paper and set aside.

Measure out the milk and add the vanilla to the milk, stir to combine, and set aside.

In a small bowl, add the sugar and cinnamon, stir to combine, and set aside.

Add the flour, baking powder, cream of tartar, salt, and 1 tablespoon of sugar to the bowl of your food processor. Pulse 3-4 times to mix everything together.

Add the cold cubed butter to the food processor and pulse until the mixture resembles coarse crumbs, about 6 times.

Slowly add the milk/vanilla mixture to the flour mixture. Pulsing to combine the ingredients making sure not to over-mix the dough.

Once the dough has just come together but you still see some crumbs not attached, turn the dough out onto a lightly floured surface.

Bring the dough together and roll out the dough so it’s about 1 inch thick. Sprinkle a small portion of the cinnamon sugar over the top of the dough.

Fold the dough into thirds making sure to sprinkle more cinnamon sugar over the area that doesn’t have any cinnamon sugar on it.

Roll the dough out to 1 inch thick again and sprinkle the remaining amount of cinnamon sugar over the top.

Cut the dough into 2-inch biscuits placing them on the prepared baking sheet.

When you run out of dough to cut into, gently bring the dough together and cut out a few more biscuits.

Bake at 450 degrees F (or 232 degrees C) for 8 minutes or until the top is golden brown.

While the biscuits are baking, add the powdered sugar and the remaining milk to a bowl. Stir to combine.

When the biscuits are done baking, drizzle the icing over top and serve immediately.