Before I started working on the cake batter, we generously coated a pan with softened butter, seasoned the pan with granulated sugar and arranged a couple cupfuls of bouncy cranberries on top. Don't be stingy with the butter here - two tablespoons will seem like too much, but it is not just used for release of the cake. As it bakes, the butter will melt down with the sugar to help create a shiny and sweet, yet still tart, ruby sauce on top.
While there is nothing unusual about the preparation of the batter for this festive cake, it is given a bright boost thanks to the addition of tiny shreds of zest from a fresh lime. No limes around? Lemon would be fine as well - you're just looking to add an lingering note to give the cake some dimension. Once dolloped on top of the cranberry layer, the cake is baked until it has risen and taken on a gratifying golden hue - the toothpick test should come back with a few moist crumbs attached.
When done, you'll want to let the cake cool for just ten minutes and then you need to flip it out - you want to do this while the sauce underneath the cake is still warm so it will release. While the cake slipped right out for us, if you did have a piece or two that got left behind on the bottom of the pan, there is enough sauce that you could patch them back on, if needed. I sent the cake in whole, so I didn't get a chance to taste it before everyone else, but Jeff stashed a small chunk for me to try when he got home - so good! I liked how the cake was sweet and moist, with that subtle hint of lime coursing through, but what really set this off was that sticky cranberry topping with its tart attitude. Next time, I think a soft dollop of fresh, lightly sweetened whipped cream, spiked with a little more zest perhaps, would be an appropriate way to finish this off with a bang!
Cranberry Upside-Down Cake