You can see why this is known as an orange “stained glass” cake. It has a very unique presentation. Also it tastes terrific, which is always a plus. It’s very creamy and Christmas-y with all the candied orange, and delivers a slight alcohol kick. A perfect light closer to a winter evening meal.
You’ll need a couple of days to prep the components for this. The génoise and candied oranges (and maybe also the pastry cream for the diplomat cream) should be made at least a day ahead. Candy the oranges by combining the sugar and the water in a small saucepan.
Bring that mixture to a boil, whisking once or twice, then add the orange slices. I used a meat slicer to get very thin, even slices, but a mandolin also works, as does a good steady hand.
Simmer the oranges for two hours until they look about like this. Pour the contents of the pan into a bowl and let them sit out overnight.
The next day, prepare your mold. A deep pie pan works great for this recipe, provided you line it with plastic wrap like I’m doing here. You want to oil the plastic very lightly…
…then scatter on a dusting of granulated sugar. What does this do? It creates a thin layer of syrup which will give the cake a glistening appearance when it’s unmolded. Tap it around, then pour off the excess.
Line your mold with your best slices. If your slices have any tears or holes in them you’ll want to double them up to prevent the cream from peeking through. Chop the rest of the slices finely and set them aside.
Once that’s done, prepare your génoise cake. Trim off the top so you won’t risk having any brown showing through the cream layer. You don’t have to get every last speck of brown off. I like to freeze the génoise layer ahead of time so it’s easier to cut.
Trim up the sides for the same reason, though odds are you’ll need to do that anyway since the cake layer will probably be a little wide to fit the pie plate.
Now cut it in half horizontally. I know, sounds scary, but it really isn’t. just make a shallow cut along the belt line of the layer, going around and around, slowly cutting deeper until….
…you cut through the very center.
Keep your hand on top the whole time like this though, K?
And you’ll have two nice thin layers.
When those are prepared, plop about 2/3 of the diplomat cream into the mold.
Very gently, so as not to push the orange layers around, spread the cream, pushing it up the sides of the mold.
Apply one of the cake layers and using the reserve syrup from the oranges — spiked with a couple tablespoons of Grand Marnier if that’s your thing — dab it around.
Fold the reserved chopped, candied orange into the remaining diplomat cream and spread that on the layer.
Now dab more syrup on the other layer, on the cut side.
Flip it over onto the mold. It has parchment on the bottom from the cake pan. Peel that off at this point.
Apply a plate or a cake circle like I have here and press down firmly. Put something relatively heavy on the top (a few cans of peaches or something), then put the mold in the fridge for at least a couple of hours.
To unmold the cake, flip it over onto the cake circle or onto a platter.
Gently remove the pie pan. At this point you’ll want to put the cake in the freezer for about half an hour to firm the cream on the very outside of the cake. Then gently…oh so gently…peel back the plastic wrap.
You might have a little dripping syrup or a couple of cream spots to smooth, but here’s roughly what you’ll have.
Definitely serve this at the table, since you don’t want to miss out on the oohs and ahs.