This cake was inspired by the marble cakes, typically bundts or loaves, you’ll see in grocery store bakeries. There’s even one photographed on the nonstick spray Baker’s Joy canister. My senior year of high school could have been measured in slices of Starbucks’s iteration of this cake (to be devoured with a venti caramel-flavored coffee, thank you so much).
My sweet tooth has evolved since those years—I still crave desserts something furious, but I don’t like my cakes so sweet. Store-bought marble cakes are always saccharine, but the look of them haunts me. So I decided to make one, but instead of dark cocoa powder—chocolate is usually the contrasting flavor and color in these cakes—or raspberry, which usually just means red food coloring, I went with blueberry.
The best way to harness the flavor of fruit with no additional moisture is to use freeze-dried and ground. If you close your eyes, this cake tastes like a blueberry muffin, which is extremely comforting. However it’s just as good with other fruit powders, from strawberry to pineapple. Freeze-dried blueberries or blueberry powder can be purchased in some stores or online. While you could top this loaf cake with a glaze made with powdered sugar, milk, and a bit of extra freeze-dried blueberry powder, as I did when I was first testing this cake, I found it ultimately unnecessary; instead, I opt for showering the cake with a mixture of crunchy demerara sugar and flaky sea salt. I urge you to top any loaf cake or quick bread with the same mixture. —Rebecca Firkser
- Prep time 30 minutes
- Cook time 1 hour
- Makes one 8.5x4.5-inch or 9x5-inch loaf cake, or two 5.5x3-inch loaf cakes
Nonstick cooking spray
freeze-dried blueberries (or about 2 1/2 tablespoons freeze-dried blueberry powder)
refined or unrefined coconut oil, at room temperature (it should feel like softened butter)
flaky sea salt
- Heat the oven to 350ºF. Spray a 8.5x4.5-inch, a 9x5-inch, or two 5.5x3-inch loaf pans with cooking spray, then line with parchment paper, leaving an overhang on the longer sides of the pan. Grind freeze-dried blueberries in a clean coffee or spice grinder, food processor, or high-power blender until you’ve made a very fine powder. Transfer to a small bowl.
- In a medium bowl, whisk together flour, baking powder, salt, cardamom, and cinnamon.
- In a large bowl, use an electric mixer at medium speed to cream the sugar and coconut oil until well combined, about 3 minutes. Add eggs one at a time, beating well between each addition, then scrape down the sides of the bowl and beat until the mixture is pale and very fluffy, about 3 minutes.
- In a small bowl, whisk together the sour cream and oil (it may not combine completely, that’s OK). Reduce the mixer speed to low and beat in the dry ingredients in 3 additions and the sour cream mixture in 2 additions, making sure each addition is fully incorporated.
- Scrape half the batter into the bowl that used to contain dry ingredients, then beat in the reserved blueberry powder at medium speed until completely combined.
- Spoon large scoops of both colors of batter into the loaf pan (divide among both pans if using the mini pans) alternating colors on top of one another. Use a chopstick to run through the batter, swirling from one end of the pan to the other to make a marbled pattern—don’t overdo it, but get in there. Tap the pan on the counter a few times to settle the batter. Top with demerara sugar and flaky sea salt.
- Bake until a tester poked into the center of the cake comes out clean, 50 to 60 minutes for 8.5x4.5-inch pan, 45 to 55 minutes for 9x5-inch pan, or 30 to 40 minutes for two 5.5x3-inch pans. Let the cake cool in the pan for at least 20 minutes, then lift the sides of the parchment to pull it out. Let the cake cool completely before slicing.
- Tightly wrapped, the cake will keep at room temperature for one week, or frozen indefinitely.