Preheat oven to 350°. Butter and flour a 9×9 inch baking pan. Make topping by combining 1/2 cup sugar, pecans, 1 T. melted butter, cinnamon and 1/2 tsp. nutmeg in a bowl. Set aside. Whisk buttermilk, eggs, vanilla, and orange peel in a bowl and set aside. Combine flour, baking powder, remaining sugar and nutmeg in a food processor or bowl. Add 7 T. chilled butter and process until mixture resembles coarse meal. Add buttermilk mixture and process until just blended. Fold in berries and transfer to prepared pan. Sprinkle topping over. Bake about 1 hour 5 minutes, or until tester comes out clean when inserted into center. Cool cake completely in pan on rack.