This orange marble cake is another citrusy twist on the classic recipe. To make this cake, you will need all-purpose flour, baking powder, salt, unsalted butter, granulated sugar, eggs, vanilla extract, milk, orange zest, and orange juice. The cake batter is divided into two parts, and one part is mixed with orange zest and juice to create the orange batter. The two batters are then swirled together to create the marble effect. This cake is perfect for any occasion and is sure to impress your guests.