Peach and Blueberry Crumb Pie

• Butter, for greasing the pie dish

Filling:

• 1/4 cup quick cooking tapioca pearls, such as Minute Tapioca
• 1 pound frozen blueberries, thawed and drained, or 1 1/2 cups fresh blueberries
• 1 pound frozen peaches, thawed, or 3 large fresh peaches, pitted and thinly sliced
• 1/2 cup brown sugar
• 2 tablespoons fresh lemon juice
• 2 teaspoons pure vanilla extract
• 1 1/2 teaspoons ground cinnamon
• Zest of 1 large lemon
• One 9-inch unroll-and-bake refrigerated pie crust
• 1 egg white, lightly beaten

Topping:

• 1/2 cup slivered almonds
• 1/2 cup (1 stick) butter, cut into 1/2-inch pieces, chilled
• 1/2 cup quick cook oats
• 1/2 cup almond flour
• 1/2 cup brown sugar