- Nonstick cooking spray, for greasing
- 3 medium plums, pitted and sliced into 8 wedges
- 21/4 cups granulated sugar, divided
- 2 sticks unsalted butter, melted
- 2 eggs
- 3/4 cup whole milk
- 1 lemon, zested (2 teaspoons)
- 2 cups all-purpose flour
- 2 teaspoons dried lavender flowers, ground
- 2 teaspoons kosher salt
- 1/2 teaspoon baking soda
- 1/2 teaspoon baking powder
Preheat oven to 350°F. Grease a high sided 8-inch cake pan with cooking spray and line with parchment. Line the bottom of the pan with a concentric circles of plum slices then arrange the remaining in the center.
In a medium saucepan, combine ¾ cup sugar with 2 tablespoons water over medium-high heat. Cook, shaking the pan if needed, until an amber caramel forms, 5-6 minutes. Immediately pour over peaches in an even layer.
In a large bowl, whisk remaining 1½ cups sugar with butter until smooth. Add eggs and whisk until incorporated, followed by milk and lemon zest.
Add remaining ingredients to bowl and fold until just incorporated, then pour over the caramel-coated peaches. Bake until the top is golden and a toothpick inserted into the center comes out clean, 60-70 minutes.
Let cool 10 minutes, then run a paring knife along the edges of the cake. Place a plate over the cake pan and invert, discarding parchment paper. Let cool slightly, then serve warm.