Ingredients:
- 3 cups (450g) fresh peaches, peeled and diced into 1/2 inch cubes
- 1 tbsp (15ml) fresh lemon juice
- 2 tsp (5g) ground Korintje cinnamon
- 1 tbsp (8g) cornstarch
- 3 cups (375g) all-purpose flour, sifted
- 1 ½ tsp (7g) baking powder
- ½ tsp (3g) baking soda
- 1 tsp (6g) fine sea salt
- 1 cup (225g) unsalted butter, softened to 65°F
- 1 ½ cups (300g) light brown sugar, packed
- ½ cup (100g) granulated white sugar
- 3 large eggs, room temperature
- 1 tbsp (15ml) pure vanilla bean paste
- 1 cup (240ml) full-fat buttermilk, room temperature
- ½ cup (115g) unsalted butter (for frosting)
- 1 cup (200g) dark brown sugar (for frosting)
- 1/3 cup (80ml) heavy whipping cream (for frosting)
- 1 tsp (5ml) vanilla extract (for frosting)
- 2 cups (240g) confectioners' sugar, sifted (for frosting)
Instructions:
- Toss the diced peaches with lemon juice, cinnamon, and cornstarch in a small bowl. Set aside for 15 minutes to macerate and allow the cornstarch to bind the juices.
- Preheat oven to 350°F (175°C). Grease and flour a 9x13 inch professional-grade aluminum baking pan.
- In a medium bowl, whisk together the sifted flour, baking powder, baking soda, and sea salt.
- Using a stand mixer with a paddle attachment, cream 1 cup of softened butter with 1.5 cups light brown sugar and 0.5 cup granulated sugar on medium-high speed until light and aerated (about 4 minutes).
- Add eggs one at a time, beating well after each addition. Incorporate the vanilla bean paste.
- Reduce mixer speed to low. Add the flour mixture in three parts, alternating with the buttermilk, beginning and ending with the flour. Mix just until combined.
- Gently fold the macerated peaches and any accumulated juices into the batter by hand.
- Spread batter into the prepared pan and bake for 45 minutes, or until a tester inserted into the center comes out clean.
- Prepare the frosting: In a heavy-bottomed saucepan, melt 0.5 cup butter with dark brown sugar and heavy cream. Bring to a gentle boil for 2 minutes, then remove from heat. Whisk in vanilla and confectioners' sugar until smooth.
- Pour the warm frosting over the cake immediately and smooth with an offset spatula. Let set before slicing.