If you haven’t already, you really must meet my friend Ashley. She used to run a dessert catering company, and a few years ago, I got to work for her as a sort of informal apprentice.
This came about almost accidentally, but was a pretty sweet deal (if you’ll pardon the pun), because though I showed up intending to chop chocolate and wash dishes, more often than not she let me do the fun stuff, like pipe polka dots on wedding cakes and liberally sample everything within reach – for educational purposes, of course.
At the time, her eldest son was six or seven months old, and Lydia was at least a year from being born. Since then, Ashley and I have hatched a combined four children, in two rounds of synchronized pregnancies: the first time, we shared a due date. The second time, we were within days of sharing a due date. Both times, the babies came five days apart.
I know, that has nothing to do with Rainbow Chip Cake. But trust me, we’re getting there.
My love of bittersweet chocolate stems directly from Ashley. Her recipe for tart dough is still the one I turn to, and her chocolate chip cookies are the ones that I make every single time I bake cookies. While pregnant with Sarah, I craved Ashley’s salted caramel macarons, which was unfortunate, because by that time she had moved to Seattle and started her blog.
And that, at last, brings me to Rainbow Chip Cake. In honor of her husband’s birthday, Ashley pulled together this incredible recipe, which left me wishing that a) she still lived in my town, and b) my daughter could eat eggs. Nonetheless, the second I saw photos of that cake, I knew that I’d be serving this at my birthday as well as Lydia’s, no matter how much creativity it took to make that happen.
I based my cake upon on the Bittersweet Chocolate Cake recipe, so the cake itself is dairy-free, but because I can’t vouch for the white chocolate chips, I call this Almost Dairy-Free Cake. The frosting is decidedly not dairy free, I’m afraid. But if you can stomach it, it’s incredible – comparable to Ashley’s Cadbury Eggs, really, and not nearly as messy to make.
Homemade (Almost Dairy-Free) Rainbow Chip Cake
For the cake:
3 c. unbleached, all-purpose flour
1/2 c. cake flour (or more all-purpose flour)
2 c. sugar
2 tsp. baking soda
1 tsp. salt
1/2 c. canola oil
2 Tbl. white vinegar
1 Tbl. vanilla extract
2 c. cold water
For the frosting:
3 sticks butter, room temperature
8 oz. cream cheese, also room temperature
4 cups powdered sugar, sifted
1-2 Tbl. heavy cream (or whole milk: I used it, and the frosting was still fabulous)
¼ tsp. salt
1 ½ tsp. vanilla extract
For the rainbow chips:
12 oz. white chocolate, finely chopped
food coloring, in four colors of your choice
First, make the rainbow chips. Over a double-boiler, melt white chocolate. (Alternatively, throw it in the microwave for 20 second increments, stirring well between sessions, until melted and smooth.)
Divide chocolate into four small bowls. Add desired amount of food coloring to each bowl, warming briefly in the microwave if white chocolate begins to stiffen. On a parchment-lined baking sheet, spread white chocolate into rectangles ¼” thick. Chill completely.
Once cool, chop into pieces approximately ¼” square – though, really, the size is up to you. It’ll be pretty and tasty no matter what. Store these bad boys in a Ziploc bag until you’re ready for them. They’ll be good for a while.
Next, make the cake. Preheat your oven to 350-degrees. Grease two 8” cake pans with butter, and line bottoms with parchment (for the record, I really do think this is worth the trouble).
Whisk dry ingredients together in medium bowl. Measure oil in a liquid measuring cup, then add vinegar and vanilla. Stir to combine.
Add oil mixture to dry ingredients and whisk until the mixture resembles a coarse meal.
Add water and stir vigorously until lumps are mostly gone and the flour is completely incorporated.
Last, but absolutely not least, add ½ c. of the rainbow chips (or more, if you feel so inclined) and stir well.
Pour batter into prepared pans and bake for 30-35 minutes, until cake bounces back nicely when pressed with a fingertip. Cool completely before removing from pan.
Note: This cake keeps beautifully when well-wrapped with Saran wrap, so feel free to make it a day or two ahead and let sit at room temperature. If you’re really ahead of the game, store wrapped cakes in the freezer for a week before using. Let thaw completely before frosting, though.
Now, for the frosting: in the bowl of a stand mixer, cream the butter and cream cheese until smooth. On low speed, add the powdered sugar. As you go, you might give it a taste (as though you needed any extra incentive) – depending on your inclination, you may not want to add the full 4 cups. Remember, the white chocolate will sweeten the frosting, too, so add the sugar to taste.
Next, add the cream (or milk), 1 Tbl. at a time. Add salt, then vanilla, scraping down the sides of the bowl to make sure that all ingredients are fully incorporated.
Finally, add the rainbow chips. Stand back and admire the beauty of your rainbow-studded frosting. Then lick the beaters (it’s in the recipe, so you’re just following instructions, right?).
Now, everyone has their preferred method of frosting cakes, but here’s mine (never mind the photos – I was feeling fancy that day): put the first layer on your favorite cake plate, because you might be like me and find them unbearably fun to collect. Slather on a goodly amount of frosting, ignoring the sides of the cake completely.
Put the next layer on top, making a beautiful frosting sandwich, and top that with another goodly amount of frosting (again, ignoring the sides – I like to let the cake peek through, especially when it’s this pretty). If you have any extra rainbow chips, sprinkle those over the top of the cake.
If you have any extra frosting (which you almost certainly will), put it in a bowl to serve alongside the cake, for those of your guests who don’t mind enduring a self-inflicted sugar coma. They will bless and curse you in the same breath, but they won’t deny that this cake is delicious.