• Preheat oven to 425°F. Butter an 8-inch round cake pan.

For the fruit

• Peel and slice peaches and place in an even layer on the bottom of the pan.
• Sprinkle with sugar, nutmeg, and lemon zest. Drizzle lemon juice over the peaches, then dust with the flour. Pour melted butter over the top and set aside.

For the batter

• Combine almonds, sugar, baking powder, and salt in the bowl of a food processor. Process until the almonds are ground. Add flour and pulse to mix.
• In a medium bowl, whisk together egg, milk, butter, and extract. Add flour mixture and stir to combine.
• Spread batter over peach mixture.
• Bake 25 to 35 minutes, or until a skewer inserted in the center comes out clean.
• Cool 10 minutes, then invert onto a serving plate.