Zucchini Cake with Blackberry Frosting
It’s summer. It’s sweltering, but almost every fruit and vegetable in sight is fresh. (Except blood oranges- I had some crazy ideas for blood oranges for this cake, but those were not available.) Instead I went for ripe, sweet summer blackberries. That bright pink frosting you see in that picture up there- that is all fresh blackberry. Absolutely no food coloring or extracts used.
I explored Austin for the first time a few weeks ago (I know, I’m a fraud of Texan having never been to Austin), and I fell in love with some crazy flavor combinations. Austin’s chefs are inventive, inspiring, and they value fresh local ingredients. Plus, summer is farm-to-table’s high season. I tried to capture the inventive spirit of Austin in a cake packed with produce.
I used fresh zucchini and a ripe banana in the cake for moistness, earthiness, and sweetness. Toasted walnuts were added for crunch. Blackberries give the frosting an amazing flavor that goes perfectly with the zucchini cake (not to mention the color). And finally, an imperceivable touch of key lime zest gives the sweet frosting the tang it needs.
Now, the original recipe looked a little different. This is in my mom’s handwriting, smudged from years of use. She got the recipe from a coworker, who inherited it from her grandmother. We’re going back at least 3 generations with this cake. I kept the spirit of the old recipe- simple and delicious- but, like most farm to table dishes, a little more wholesome.
Banana and creamy yogurt are good, hearty substitutes for oil. I only need a tiny bit of butter for flavor. I used white whole wheat flour, perfect for a moist flavorful cake reminiscent of the best zucchini bread. And, as usual, cinnamon is a necessity (at least in my book). Real sugar is also a necessity and sometimes just cannot be substituted.
Zucchini, just like the carrot in carrot cake, is fabulous for moisture and flavor. You could use zucchini and carrot in this cake and it would be delicious. Make sure you find the smallest holes on your grater to make tiny shreds of the squash. No one wants a big chunk of vegetable in their cake.
Some finely chopped walnuts join our thick batter. Toasting them amplifies their flavor immensely, and it only takes 8 minutes!
While the cake is baking I get going on my blackberries. They get all blended up with a touch of lime and then pushed through a sieve to get rid of all those seeds. This liquid blackberry juice is then poured into a saucepan. There it slowly simmers and reduces until those 4 cups of blackberries turn into just about 5 tablespoons of blackberry flavor.
That deep red liquid above it’s all that’s left of the blackberries, but it packs a punch. Softened butter and good vanilla bean paste are blended with heaps of powdered sugar and blackberry, and you get this:
An aggressively pink, all-natural icing that you want to eat with a spoon. This makes plenty to ice a two-layer cake and have some left over for tasting. Once our cakes are cool and happy, they can be frosted.
My decorating skills are minimal, at best, but this is not a wedding cake or even a birthday cake. It’s a farm-to-table inspired, seasonal special. So a little abstract decoration is fine with me. Just a touch of lime zest on top keeps me looking kinda fancy. And the final step:
Devour.
I know it’s the season of ice cream cones and hot dogs (both things I love), but next time you drive by a produce stand, stop and smell the peaches. Put them in a frosting (delicious, by the way)… or don’t. Don’t make plans for dinner- just buy some fresh vegetables and experiment. Better yet, get fruity and creative with your dessert.
If you’d like some more weird, delicious ideas of what to do with dessert, look here: bakinginblackandwhite.com
You can learn more about me, my antique cookbooks, and classic recipes.
(You can also print my recipes and see my Instagram, where I pictures of the food I eat on my travels. And I’m going to Italy soon so it’ll be worth it! Excessive pasta pics to come.)
Zucchini Cake with Blackberry Frosting
Makes: 2 9-inch layer cakes + plenty of frosting, Time: 1 hour prep, 25 min baking
For the cake: 3 cups white whole wheat flour (or all purpose), 1 tsp baking soda, 1 1/4 tsp baking powder, 1/2 tsp salt, 1 1/2 tsp cinnamon, 1 cup white sugar, 1 cup light brown sugar, 3 tbsp melted and cooled butter, small ripe banana, 3 eggs, 3/4 cup full fat yogurt, 1 tsp vanilla, 3 cups finely grated zucchini, 1/4–1/2 cup finely chopped toasted walnuts
For the frosting: 4 cups fresh ripe blackberries, zest of 4–5 key limes (or 1 regular lime), 2 tbsp granulated sugar, 3/4 cup softened butter, 4–5 cups powdered sugar
1. Preheat oven to 325 degrees Fahrenheit. Line the bottoms of two 9-inch cake pans with parchment paper and grease well with nonstick baking spray. Set aside.
2. In a large bowl, beat together sugars, butter, yogurt, and vanilla. Add the mashed banana and eggs, one at a time. Beat until well combined.
3. Finely grate the zucchini until you have 3 cups. (For me this was one very large zucchini and one small.) Place the grated zucchini in a tea towel and gently squeeze to drain some of the excess moisture.
4. Fold zucchini into blended wet ingredients.
5. Sift together flour, baking soda, baking powder, cinnamon, and salt. Gradually add to blended wet ingredients, stirring until just combined. Fold in finely chopped toasted walnuts.
6. Divide the batter evenly between the two prepared cake pans. Bake at 325 degrees Fahrenheit for 30 minutes, or until a skewer inserted into the middle of the cake comes out clean and it doesn’t appear jiggly.
7. While the cake is baking, prepare the frosting. In the bowl of a food processor or blender, purée the blackberries with the lime zest. Push the purée through a fine-meshed sieve into a small saucepan. Bring the mixture to a simmer over medium-high heat. With the mixture begins to bubble, reduce heat to medium and add granulated sugar. Let mixture simmer until greatly reduced (to about 5 tbsp- up) and thickened; then place in small container and refrigerate to cool.
8. In a medium-sized bowl, blend together softened butter, vanilla extract, and 2–3 tbsp cooled blackberry mixture. Gradually add powdered sugar alternately with remaining blackberry mixture until you get an easily spreadable buttercream.
9. When the cakes have cooled, you can trim any excessive domes and ice with your frosting. Top with a little lime zest if you’d like.
