Buttermilk Tres Leches Cake

The beauty of a tres leches cake is that it is perennial in its appeal. Cold, light and yet still decadent in the summer, comforting and familiar in the colder months, it is a cake for all occasions and seasons. Don’t be afraid to engage in a little experimentation and play. Adding rum or other seasonings or spices is perfectly acceptable. But don’t skimp on the refrigeration and soaking time. You’ll be glad when your cake is optimally chilled and moist to the core.

Ingredients

• Nonstick baking spray (such as Baker’s Joy), for the pan
• 1.5 cups/215 grams all-purpose flour
• 0.6666666666666666 cup/109 grams coarse cornmeal
• 1.5 teaspoons baking powder
• 1 teaspoon coarse kosher salt, such as Morton (or use 1 1/2 teaspoons kosher salt)
• 6 large eggs
• 0.6666666666666666 cup/133 grams granulated sugar
• 0.6666666666666666 cup/146 grams light brown sugar
• 0.3333333333333333 cup/80 milliliters vegetable or canola oil
• Zest of 1 orange, grapefruit or lemon
• 1 teaspoon vanilla paste or extract
• 2.6666666666666665 cups/630 milliliters heavy whipping cream
• 1.75 cups plus 2 tablespoons/595 grams sweetened condensed milk, about 1 1/2 (14-ounce) cans
• 1.3333333333333333 cups/320 milliliters whole cultured buttermilk
• 1.5 teaspoons vanilla paste or vanilla extract
• 0.5 teaspoon ground cinnamon
• Salt

Steps

1. Heat the oven to 325 degrees. Spray a 9-by-13-inch baking pan with nonstick baking spray and set aside.
2. Prepare the cake: In a medium bowl, combine the flour, cornmeal, baking powder and salt and whisk until well incorporated.
3. In the bowl of a stand mixer fitted with the whisk attachment, beat the eggs and both sugars on medium-high until well combined and incredibly fluffy, 3 to 4 minutes, scraping the sides and bottom of the bowl about halfway through. (Drape a towel over the top of the mixer if needed to contain splashing.)
4. With the mixer on low, add the oil, citrus zest and vanilla paste, beating well and scraping the bowl intermittently for the first turns. Turn the speed up to medium-high and beat until fluffy, 3 to 4 minutes more. 
5. On low speed, add the dry ingredients to the bowl. Mix on medium to high speed until incorporated, scraping the bottom and sides of the bowl once to incorporate everything.
6. Pour the batter into the prepared pan and spread evenly. Thump the pan on the counter a few times to get out any air bubbles. Bake until a cake tester inserted in the center comes out clean, 30 to 40 minutes.
7. While the cake bakes, make the soak: In a large bowl, whisk together the cream, sweetened condensed milk, buttermilk, vanilla paste, cinnamon and a medium pinch of salt until well incorporated; set aside.
8. Allow the cake to cool in its pan on a rack for 5 minutes before handling. Then, with a skewer, poke several small holes all over the cake. 
9. Gradually pour the soak over the still warm cake (about a cup at a time), allowing it to sit until it absorbs. Continue adding and soaking the cake and letting it absorb until you use most, if not the entirety, of the soaking liquid. This soaking method will take about 1 to 2 hours as it absorbs. Cover the cake very well with foil, tenting it a little so the foil doesn’t touch the top of the cake, and refrigerate for at least 4 hours, but preferably overnight. Cut and serve the chilled cake directly from the pan.