To prepare a rhubarb strawberry herb crumble pie recipe, first you need to prepare the ingredients for the pie. First, you'll need the following ingredients: 2 tablespoons of sugar 1 tablespoon of granulated sugar 1/2 cup of butter 1 teaspoon of ground cinnamon 1/2 teaspoon ground nutmeg 1 tsp. ground cloves 14 cup chopped fresh thyme 2 teaspoons ground allspice 1/4 cup ground cardamom Instructions: Preheat the oven to 350 degrees F (180 degrees C). Grease and flour two 9-inch pie shells with butter. In another large bowl, combine the flour, baking powder, sugar, salt and cinnamon. Add the wet ingredients to the dry ingredients and stir to combine. Pour the mixture into the crust and bake for 35 to 40 minutes or until the top is golden brown. Let cool before cutting into squares. Serve warm with vanilla ice cream or whipped cream.