• First make the cinnamon sugar filling by mixing together the sugar, softened butter, and ground cinnamon until a thick and smooth paste forms. Set aside for later.

Make the scone dough

• Add the flour, sugar, baking powder, and salt to a large mixing bowl and whisk together.
• Next, cut the cold vegan butter into chunks. Then, add it to the bowl of dry ingredients and use a pastry cutter to "cut" the butter into the dough until you have a crumbly mixture. You can also use a fork to do this step, though it will take longer.
• Then, add in the oat milk and vanilla. Use the pastry cutter or your hands to combine into a shaggy dough. The shaggy dough will be flaky and crumbly, yet should still stick together when pressed.

Shape the scones

• Line a baking sheet with parchment paper and turn the dough out onto the baking sheet. 
• Next, form the dough into a rectangle that is about 2 inches in height.
• Cut the rectangle in half. Then, use a spatula to add the cinnamon sugar filling to one half of the rectangle.
• Take the dough without the filling and place it onto the half with the filling. Then, press the edges together as best you can to seal the dough.
• Place the baking tray of scone dough in the freezer for about 10-15 minutes before slicing. While the tray is in the freezer, preheat your oven to 400F.

Bake the scones

• Once the oven has preheated, remove the tray of scones from the freezer and cut into 8 evenly sized squares. Spread the scones on the parchment-lined baking tray so that they are at least 2 inches apart.
• Add the tray of scones to the oven and bake for 18-20 minutes until the scones are browned on top and cooked through.
• Remove the scones from the oven and let them cool completely before topping with the icing.

Make the icing

• Once the scones have cooled, make the icing. Add the powdered sugar to a bowl and whisk in the oat milk and vanilla until a thick icing forms.
• Drizzle the icing over the scones and let the scones rest for about 5-10 minutes until the icing hardens. Serve and enjoy!