Rum-Scented Marble Cake

Marble cakes are both homey and festive. A marble cake looks slick when you slice into it and reveal the delicate pattern created when the two batters are swirled together. My first experience working with this type of mixture came about as the result of a marbled chocolate terrine that appeared first in the pages of the old Cook's Magazine, and then in my chocolate book. Everything about it was right—the texture, the flavor, the quantity of mixture in relation to the mold—everything, that is, except the marbling. Even when I barely mixed the white and dark chocolate mixtures, what I got was a few streaks of dark and white, and mostly a muddy combined color. After several frustrating attempts, I realized that I had too much dark chocolate mixture and I recast the recipe so there was twice as much white chocolate as dark and the terrine marbled perfectly. So this marble cake is proportioned in the same way: Rather than dividing the base batter in half, I like to remove about one third of it and add the chocolate. Thanks to my old friend Ceri Hadda, who shared her mother's recipe years ago.