1. Preheat oven to 350 degrees. Grease a 9×13 rectangle cake pan.
2. Add dry cake mix, coffee creamer, milk, oil and eggs to a mixer bowl and beat until smooth.
3. Pour batter into cake pan and bake for 20-25 minutes, or until a toothpick comes out with a few crumbs.
4. Allow cake to cool for about 10 minutes.
5. While cake is cooling, melt butter in a bowl in the microwave.
6. Add brown sugar to melted butter and whisk to combine.
7. Microwave butter and sugar for about 30-40 seconds more, until sugar is dissolved, whisking about half way through.
8. Add the sweetened condensed milk and cinnamon to the butter mixture and mix until combined.
9. Poke holes in the warm cake with the end of a wooden spoon or something similar.
10. Pour mixture over cake.
11. Place cake in refrigerator for 2-3 hours while it cools and soaks up mixture.
12. To make the icing, cream the butter.
13. Add 1 3/4 cup of powdered sugar and mix until smooth.
14. Add the whipping cream and vanilla and mix until combined.
15. Add remaining 1/4 cup of powdered sugar and mix for 3-4 minutes, until light and fluffy.
15. Ice cake and top with cinnamon chips, if desired. Store cake in refrigerator.