Next, I piped the filling in with a pastry bag.
Then I repeated a layer of batter, leaving a little headspace at the top for batter expansion. I baked them at 350 degrees for 15 minutes, until they were uniformly golden, allowed them to rest in the pan for about 10 minutes, then loosened them with a toothpick to remove them to a rack to cool.
Last of all, once they were totally cooled, I whipped up a small batch of frosting out of 4 ounces of cream cheese, 2 T. butter, 1 t. vanilla and 1 cup powdered sugar, and piped it on top of the cakes.
Cute, eh? They were tasty, though different in texture and taste from a batch cooked in a large bundt pan. This was due to the larger proportion of "crust" and less of the soft stuff in the middle. Also, I felt like the amount of cream cheese filling was wimpy and next time I'll pipe more in. I wound up using about half the batter to make 12 of these, and 1/3 of the filling amount. The remaining filling and batter I simply baked in a round pan. I think they'd make delightful filled cupcakes as well. I ate a couple of them the next day and felt like the flavor was even better. Be sure to store these in the refrigerator.