In this loose interpretation of my mom’s chocolate chip-sour cream bundt cake, sweet rice flour, all-purpose flour and a healthy amount of sour cream combine to create a rich, plush cake with a moist and structured crumb. Baked in a versatile 8-inch square pan and generously studded with melty semisweet chocolate chips, this snackable cake is simple but surprisingly decadent, a reminder that at the end of the day, cake should taste good and be a joy to eat. Enjoy a homey, comforting slice with your fingers or a fork — there are no rules here.
Position an oven rack in the middle of the oven and preheat to 350 degrees F. Lightly grease an 8-inch square pan with nonstick cooking spray. Line the bottom with parchment, leaving a 2-inch overhang on the sides (to make it easier to remove the cake after baking) and grease the parchment.
Combine the all-purpose flour, sweet rice flour, baking powder, baking soda and salt in a medium bowl and whisk until combined.
Beat the butter in a large bowl with an electric mixer until smooth. Add the sugar and cream the mixture until light and fluffy, 2 to 3 minutes. Scrape down the bowl with a rubber spatula. Add in the eggs one at a time, beating after each addition until combined. Scrape the bowl once more, then beat in the vanilla. Sift half of the dry ingredients over the egg mixture and beat just until combined. Beat in the sour cream and milk, then sift in the rest of the dry ingredients and beat just until the batter is smooth. Fold in the chocolate chips.
Spread the batter into the prepared pan, smoothing the surface with a small offset spatula. Sprinkle additional chocolate chips on top. Bake the cake, rotating the pan halfway through, for about 40 minutes, or until a toothpick inserted in the center comes out clean. Let the cake cool in the pan for 20 minutes, then gently loosen the edges with a small offset spatula and carefully transfer the cake (using the parchment sling to assist) onto a rack to cool completely.
When measuring flour, we spoon it into a dry measuring cup and level off excess. (Scooping directly from the bag compacts the flour, resulting in dry baked goods.)