Preheat your oven to 425°F (220°C) and line two baking sheets with parchment paper.

In a small bowl, combine toasted chopped pecans (if using), light brown sugar, and ground cinnamon. Mix thoroughly.

In a large mixing bowl, whisk together all-purpose flour, rolled oats, granulated sugar, baking powder, and salt.

Cut in the cold unsalted butter until the mixture resembles coarse crumbs with pea-sized clumps.

Whisk together milk, egg, and vanilla extract, then pour into the dry ingredients and stir until just combined.

Gently fold in the cinnamon swirl mixture into the dough, ensuring even distribution without overmixing.

Drop the dough onto the prepared baking sheets, spacing a couple of inches apart, and bake for 11-13 minutes.

Remove the scones from the oven, allow cooling slightly, then whisk together confectioners' sugar and milk to create a glaze and drizzle over scones.