Pour cider into a small saucepan. Place over medium heat and bring to a heavy simmer. Continue simmering until the liquid has reduced to 1/2 cup. This will take about 10 minutes. Pour into a bowl and refrigerate for about 30 minutes to cool down.
Preheat oven to 425 degrees F. Once cooled, whisk in vegetable oil, milk, eggs and vanilla extract. In another bowl, whisk together flour, sugar, baking powder, salt and cinnamon. Pour liquid mixture into the dry ingredients and fold until just combined.
Spray muffin tin with nonstick spray. Portion muffin batter evenly into 12 muffins. I like to use an ice cream scoop for even portions. Bake for 12 to 15 minutes, until a toothpick comes out clean. Let cool for 5 minutes.
In a bowl, add 1/3 cup sugar and 1 teaspoon cinnamon. Melt butter in another bowl. Dip muffin tops in the butter then roll in the cinnamon sugar. Once cool, store in an airtight container for up to 5 days.