An entire cake is too much food (and temptation!) for me and my husband. Generally speaking, how do I halve a cake recipe? I have heard you can't just cut everything in half due to the way baking powder & soda react.
A particular recipe I would like to cut in half is Red Velvet Cake.
(I would then just put all the batter into one cake pan instead of 2.)
I have halved cake recipes before without issue. The most complicated thing to worry about is halving an odd number of eggs, but this question addresses that. The finished product was indistinguishable from the full recipe.
Edit
One thing to note. In your specific case, because it's a two-layer cake, halving is simple because you're only cooking a single layer. Halving other cakes, such as a pound cake, or a bundt cake involves adjustments to the cooking time. A halved cake will cook much quicker, and could possibly need a lower temperature as well as a decreased cooking time.
I halve cake recipes quite often and just round up the number of eggs. So if the full recipe calls for 3 eggs, instead of trying to figure out 1 and 1/2 I put in 2. So far, so good.
