3/4 cup (1 1/2 sticks) unsalted butter, room temperature, plus more for pan and parchment
2 1/3 cups cake flour (sifted, then measured) plus more for pan
2 1/2 cups (10 ounces) fresh black raspberries ( we like using Mac)
1/4 cup plus 1 1/3 cups sugar
1 1/2 teaspoons baking powder
3/4 teaspoon salt
1/2 teaspoon baking soda
3 large eggs, room temperature
2 teaspoons vanilla extract
1 1/2 teaspoons finely grated orange zest
1 cup well-shaken buttermilk (whole fat)
Powdered sugar (for dusting)
Position a rack in middle of oven and preheat to 350°. Butter pan; line bottom with a round of parchment paper. Butter parchment. Dust with flour; tap out excess.
Arrange berries in a single layer in bottom of pan; sprinkle evenly with 1/4 cup sugar.
Sift 2 1/3 cups flour, baking powder, salt, and baking soda into a medium bowl; set aside.
Using an electric mixer, beat 3/4 cup butter and remaining 1 1/3 cups sugar in a large bowl at medium-high speed, occasionally scraping down sides of bowl, until pale and fluffy, about 2 minutes. Add eggs, one at a time, beating well after each addition. Beat in vanilla and zest.
Reduce speed to low; beat in flour mixture in 3 additions, alternating with buttermilk in 2 additions, beginning and ending with flour mixture and beating just until incorporated. Pour batter over berries in pan; smooth top.
Bake until cake is golden brown and cake bounces back when pressed gently with fingertip, about 1 hour 25 minutes for a 9" pan and about 1 hour for a 10" pan.
Let cool in pan set on a wire rack for 15 minutes, then run a thin, sharp knife around the edge of the pan to loosen. Remove pan sides. Invert cake onto rack and remove pan bottom; peel off parchment. Dust top generously with powdered sugar and let cool completely.
| Adapted from Bon Appetit/Melissa Roberts