Preheat oven to 350°F. Grease and lightly flour a 9-inch round pan with 2-inch sides OR a 9-inch springform pan. (Preheat oven to 335°F if using dark nonstick baking pan.)
Combine flour, baking powder and salt in a large mixing bowl. With mixer set on low speed, add butter pieces, one at a time, and continue mixing until mixture resembles breadcrumbs (pea size or smaller). Add sugar, eggs and corn syrup. Mix on medium speed for 30 seconds until combined.
Spread half the batter into prepared pan. Top with sliced peaches and blueberries, reserving a few peach slices and blueberries for top of cake. Press down lightly on fruit. Sprinkle with 2 to 4 tablespoons turbinado sugar (use more or less depending on sweetness of fruit). Carefully spoon and spread remaining cake batter over fruit. Arrange reserved peach slices and blueberries on top, pressing down lightly. Sprinkle remaining turbinado sugar over top.
Bake 60 to 70 minutes, or until toothpick inserted in center comes out clean. Cool for at least 1 hour on wire rack before removing from pan. Serve warm or at room temperature.
TIP: If you can’t find fresh peaches or blueberries, try this recipe with 4 peeled, cored and sliced pears instead of peaches and/or raisins instead of blueberries.