When I made the cake, I used a 4 inch baking pan and baked the cake for 30 minutes. I used the remaining batter to make 6 cupcakes, which baked for 20 minutes.
If you would like to amp up the flavor even more, add a bit of rum extract.
You can substitute Greek yogurt for sour cream if needed.
Recipe only slightly adapted from the Martha Stewart Cakes cookbook.
The nutrition information presented on this site should be considered an estimate as the calculations will change based on the exact products you use in your own kitchen.