Add ice cream, apple pie filling, milk, caramel sauce, and cinnamon (if using) to a blender. Tip: For a thicker shake, freeze the apple pie filling for 15 minutes first.

Blend on medium speed until smooth, about 30 seconds. Scrape down sides as needed. Tip: Add 1-2 more tbsp milk if too thick.

Drizzle caramel inside serving glasses, then pour in milkshake. Tip: Swirl caramel with a spoon for a marbled effect.

Top with extra caramel and a pinch of cinnamon. Serve immediately with a spoon and straw. Tip: Garnish with a thin apple slice for flair.