Adapted from a recipe by Diane on allrecipes.com. Modified slightly to reduce fat and make it moister. Freezes well. Can be vegan if you leave out the sour cream. Can replace half the all-purpose flour with whole-wheat flour if you choose. Natural cocoa powder is preferred to Dutched; the slight astringency will cut through the sweetness and richness better. Greasing and powdering the pans helps with release; using cocoa powder instead of flour prevents tell-tale white spots on the dark surface of the cakes (but you can use flour in a pinch).
I based this on Cook's Illustrated magazine's Key Lime Bars, but substituted Jell-O Instant Sugar-Free Lemon Pudding to lower the sugar content.
You could substitute any flavor pudding you like, and leave out the lemon zest.
From the Syllabub blog at blogspot.com. Recipe #291854 and Recipe #291855 are specifically intended for use in this recipe. "Prep time" includes making and cooling the custard. Some people like to decorate their trifle with toasted sliced almonds. You could also use a handful of left-over whole fruit. Or – just leave plain. As soon as you dig into the trifle, and serve it up, it will all collapse anyway – there is no such thing as an elegant serving of trifle. For that, you would need to make individual trifles, which some restaurants do, but it definitely detracts from the debauchery.
After trying "orange fluff" posted by another chef - I was inspired to create this for myself. I love ice cream and chocolate, and I find that this a great way to curb my cravings and in generous helpings too! Great for those on low-calorie diets.