Start by preheating your oven to 400 degrees. Use non-stick cooking spray (with added flour) and spray the muffin pan or use liners.
Mix the cinnamon and sugar together in a small bowl. Divide the mixture and set aside 4 tablespoons to be sprinkled on top of the cruffins after they are done baking.
Open the puff pastry sheets (there will be 4 in total) and lay them flat on the counter. Put two aside for later as they're going to be what is used on top.
Spread 1/4 cup of the softened butter on each of the bottom two sheets. Divide the larger amount of cinnamon/sugar mixture and sprinkle that on top of the two buttered sheets. Make sure that you're covering the whole surface.
Take the two pastry sheets that you'd set aside and put them on top of the two buttered ones, creating a sandwich.
Grab a pizza cutter and cut out 6 strips that are equal in size from each one.
Roll up the slices just like you would a cinnamon roll and securely pinch the ends so that they stay closed while you're baking them. Put each rolled cruffin into a lined muffin cup and pop it in the oven to bake for 15-18 minutes.
Sprinkle on the 4 tablespoons of cinnamon sugar while they're still warm.
If you want to add icing on top, just whisk together 1 cup of powdered sugar and 3 tablespoons of milk and drizzle on top.