Preheat the oven to 350 degrees. Prepare your muffin tins by placing cupcake liners, set aside.

In the bowl of a stand mixer, combine the softened butter and sugar. Cream until smooth.

Add in the egg, Rumchata and vanilla. Mix until combined.

Add in the cinnamon, salt, baking powder and flour. Mix thoroughly - stopping the machine to scrape the sides often and mixing again.

Using a small ice cream scoop or ¼ cup measuring cup, divide the batter equally among the lined cupcake tins and fill until about ⅔ full.

In a small bowl, combine the sugar and cinnamon for the topping. Sprinkle about a half teaspoon of the cinnamon sugar mix over the cupcake batter.

Bake in the preheated oven for 14-16 minutes or until the edges are slightly browned and the center is set. Allow to cool completely before decorating.

For the frosting - in the bowl of a stand mixer, combine the softened butter, vanilla, salt, Rumchata and about half of the powdered sugar. Mix on low until combined.

Add in the remaining powdered sugar and continue to mix on low until combined. Add a splash more Rumchata at a time if needed if the mix still looks dry and crumbly.

Bump up the speed to medium and whip for an additional minute, until the frosting is smooth and fluffy looking.

Transfer the frosting to a piping bag fitted with a large star tip.

Once the cupcakes are cool, pipe a large mound of frosting on each cupcake.

Sprinkle liberally with the remaining cinnamon and sugar mixture.