Have all ingredients at room temperature, about 70°F.
Combine in a small bowl and soak for 2 hours:
Preheat the oven to 350°F. Grease and flour two 9-inch round cake pans and line the bottoms with rounds of parchment paper.
Whisk together thoroughly in a medium bowl:
Beat in a large bowl, or in a stand mixer with the paddle attachment, until creamy:
Beat in:
Beat until light and fluffy, scraping down the sides of the bowl a few times during mixing, about 5 minutes. Beat in one at a time until combined, scraping down the sides of the bowl frequently:
Add the flour mixture in 3 parts, alternating with the milk mixture in 2 parts, scraping down the sides of the bowl after each addition. Beat until just combined. Scrape the batter into the prepared pans. Bake until a toothpick inserted in the center comes out clean, 15 to 20 minutes.
Let cool in the pans on a rack for 10 minutes, then invert the cakes onto the rack, peel off the parchment, and turn them right side up to cool completely. Spread between the layers:
Dust the top with: