This cupcake is made by Honolulu, Hawaii bakery Let Them Eat Cupcakes, via their Facebook page. Contact them at 808-531-2253 and visit cupcakes808.com for more information.
And because I'd never heard of haupia until I went to Honolulu in January, here's a little definition from Wikipedia:
Haupia is a traditional coconut milk-based Hawaiian dessert often found at luaus and other local gatherings in Hawaiʻi. Since World War II, it has become popular as a topping for white cake, especially at weddings. Although technically considered a pudding, the consistency of haupia closely approximates gelatin dessert and is usually served in blocks like gelatin.