To achieve a beautiful marble effect in your marble loaf cake, pour the white batter into the baking tray first, then add the chocolate batter randomly on top. Use a knife or skewer to gently swirl the two batters together without fully mixing them. This will create the desired marbled look.

Yes, you can easily make a gluten-free marble loaf cake by substituting the cake flour with a gluten-free all-purpose flour blend. Make sure the blend contains a binding agent like xanthan gum for the best texture.

To store leftover marble loaf cake, wrap it tightly in plastic wrap or aluminum foil and keep it at room temperature for up to 3 days. For longer storage, you can freeze the cake by slicing it and placing it in an airtight container or freezer bag for up to 3 months. Just thaw it at room temperature before serving.

If you don't have buttermilk on hand, you can easily make a substitute by mixing 1/4 cup of milk with 1/2 tablespoon of vinegar or lemon juice. Let it sit for about 5 minutes until it thickens slightly, then use it in your marble loaf recipe as directed.

Marble loaf cake pairs wonderfully with a variety of accompaniments. Consider serving it with a dollop of whipped cream, a scoop of vanilla ice cream, or a drizzle of chocolate sauce. For a refreshing contrast, a side of fresh berries or a fruit compote can also enhance the flavors beautifully.