Spiced Rhubarb Crumble Pie – shushified

Ingredients

• 1 pie dough (single crust)
• ½ cup rolled oats
• ½ cup sugar
• 1/2 cup brown sugar (packed)
• ½ cup flour
• ½ tsp kosher salt
• ¼ tsp five-spice powder
• ½ cup unsalted butter
• 6 cups chopped rhubarb (1/2 in. pieces, approx 2-2½ pounds)
• ½ cup brown sugar (packed)
• 1 tsp vanilla
• ¼ tsp cardamom
• ½ cup tapioca flour