Sweet Cherry, Black Plum and Yellow Peach Cobbler

Ingredients

• 2 pounds bing cherries sweet
• 2 pounds peaches ripe yellow medium peaches
• 1 pound plums about 6, black plums
• 9/16 cup all purpose flour
• 2/3 cup granulated white sugar
• 2 teaspoons vanilla extract
• 1 teaspoon ground cinnamon
• 1/2 teaspoon ground black pepper fresh
• 2 1/4 cups all purpose flour
• 7 15/16 tablespoons granulated white sugar
• 1 1/2 teaspoons baking powder
• 1/2 teaspoon baking soda
• 1/2 teaspoon salt
• 3/4 cup unsalted butter 1 1/2 sticks or 12 tablespoons
• 2/3 cup yogurt
• 2 tablespoons half and half
• 1 large egg yolk
• 2 tablespoons granulated white sugar