Preheat oven to 375°F. Coat a 9-inch square baking pan with cooking spray.
In a small bowl, gently toss peaches with brown sugar until sugar starts to dissolve; spoon fruit into prepared baking pan.
In another small bowl, sift together flour, granulated sugar, cinnamon and salt; add egg white and combine with your fingers until mixture comes together and starts to crumble. Drop clumps of flour mixture over fruit; drizzle with melted butter.
Bake until fruit just starts to bubble, about 45 minutes. Allow to cool slightly and serve warm. Yields about 2/3 cup per serving.