|Props to my brother for arranging his cake artistically for me.|
I talked to my mom about the recipe on Easter and realized that she used to do a few things differently than I do (even though I follow the recipe that she gave me!). First, she uses cocoa powder rather than chocolate syrup for the chocolate batter. She also really marbles the chocolate and vanilla when she adds them to the pan. I just pour the chocolate onto the vanilla. Now, since I use the chocolate syrup, this has an interesting effect - the more liquidy chocolate batter ends up sinking a bit and suspending itself inside the vanilla. It does it every time. I think this looks pretty neat. But a thicker, cocoa powder flavored batter marbled with the vanilla batter would look lovely as well. I don't know how much cocoa powder would be a valid substitute - maybe 1/3 c (for 2/3 c chocolate syrup)? If you're going to experiment, let me know how it goes! I'll probably just stick with my way (unless I'm out of chocolate syrup!).
I've included a picture of my workspace for your edification. This is the majority of the counter space in my kitchen. My kitchen is actually a good size, but the counters are very narrow for some reason. When I'm doing a recipe like this one, which involves several bowls, my mixer and pans, it gets pretty crowded. I long for a kitchen island, where I could spread all this out! But until then, I'll make do with obsessively putting everything away as I finish using it.
Add the chocolate syrup to the reserved batter and beat on low until combined (it will be much more liquidy than the vanilla batter, for obvious reasons).
Pour the chocolate batter into your pan, over the vanilla. (If you wish to marble them, you can alternate ladles full of each batter into the pan until it is full, then run a knife through it to blend them a little.)
Bake for about 50 minutes, or until a toothpick comes out clean. Cool 15 minutes on a wire rack before unmolding (I think I waited slightly longer, but the cake was still a bit warm when I did it and I had no trouble).