Preheat oven to 350°F. Butter the inside of a nine-inch pie dish. Immerse peaches in boiling water for 30 seconds, then place them in cold water. Peel and slice into thick wedges and place in a large bowl. Add the orange zest, 1/4 cup of the sugar, 1/2 cup brown sugar, and two tablespoons flour. Toss well. Gently mix in the blueberries. Allow mixture to sit for five minutes. If there is a lot of liquid, add one more tablespoon of flour. Pour the peach and blueberry mixture into the baking dish and gently smooth the top. Combine 1 ½ cups flour, one cup sugar, 1/2 cup brown sugar, salt, oatmeal, and the butter in the bowl of an electric mixer fitted with a paddle attachment. Mix on low speed until the butter is pea-sized and the mixture is crumbly. Sprinkle evenly on top of the peaches and blueberries. Bake for one hour, until the top is browned and crisp and the juices are bubbly. Serve immediately, or chill in refrigerator and reheat in a 350°F oven for 20-30 minutes until warm.
Photograph by Squire Fox