Buttermilk Plum Cake

Ingredients

• 1½ cups (204 g) all-purpose flour
• 2 teaspoons baking powder
• ½ teaspoon ground coriander
• ¼ teaspoon baking soda
• ¼ teaspoon fine sea salt
• ¼ teaspoon ground cinnamon
• 8 tablespoons (113 g) unsalted butter, at room temperature
• ¾ cup (150 g) granulated sugar
• 2 large eggs, at room temperature
• ½ teaspoon pure vanilla extract
• ½ teaspoon pure almond extract
• ½ cup (120 ml) buttermilk, well shaken and at room temperature
• 8 to 10 small Italian prune plums, quartered
• 2 tablespoons light-colored jam or jelly, for the optional glaze

Instructions

1. Center a rack in the oven and preheat to 350°F (175°C). Butter a 9-inch square baking pan, dust it with flour and tap out the excess, or coat it with baker’s spray.
2. Whisk the flour, baking powder, coriander, baking soda, salt, and cinnamon together in a medium bowl.
3. In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl with a hand mixer, beat the butter and sugar on medium speed for about 4 minutes, until pale, light, and fluffy.
4. Add the eggs one at a time, beating for about 1 minute after each addition. Beat in the vanilla and almond extracts until the mixture is creamy.
5. Add half of the dry ingredients and mix on low only until they disappear. Scrape the bowl, mix in the buttermilk, then add the remaining dry ingredients and mix just until incorporated.
6. Scrape the batter into the prepared pan, smooth the top, and make sure the batter reaches the corners.
7. Arrange the quartered plums over the batter in tidy rows, skin side down, pressing them in very lightly without submerging them.
8. Bake for 38 to 45 minutes, until the cake is golden, the plums are tender and bubbling, and a tester inserted into a cake-only area comes out clean.
9. Cool the cake in the pan on a rack for 15 minutes, then run a thin knife around the edges. Serve from the pan or carefully turn out once fully cooled.
10. For the optional glaze, warm the jam or jelly with a few drops of water until fluid, then brush it over the warm plums. Let the glaze set before cutting into squares.