I love marble cake and always finding ways to improve it! The swirl turns out beautifully and the secret to that deep black chocolate batter is actually charcoal powder. It really stands out and bring the beauty of the two swirls. Of course, charcoal powder is totally optional but I highly recommend you to incorporate it if you want to impress your family and friends with this recipe. It’s been a while since I came out my marble bundt cake recipe and I have improved upon it.  This recipe is much more buttery and uses just cocoa powder. Although you may question why I didn’t use melted chocolate for the chocolate…