准备

使外壳：

• In a food processor, combine the flour, sugar, and salt, and pulse to combine. Add the butter and shortening and pulse until the mixture resembles coarse meal, about 1 minute. Transfer the mixture to a large bowl.

  Fill a measuring cup with 1/2 cup very cold water. While tossing and stirring the flour mixture with a fork, add the water 1 Tbs. at a time until the dough just begins to come together in small clumps and holds together when you pinch a little between your fingers (you may need only 1/4 cup of water).

  将面团转移到干净的工作表面上，并用手聚集。将面团轻轻揉一两次，将其分成一半，然后将两半的圆盘塑造成磁盘。将磁盘分别用塑料包裹，然后冷藏至少1小时或最多2天。

Prepare the filling:

• Position a rack in the center of the oven and heat the oven to 375°F. In a large mixing bowl, combine the rhubarb, strawberries, sugar, all the tapioca, orange juice, zest, cinnamon, clove, allspice, and salt. Toss gently to mix well, and then let sit for at least 10 minutes and up to 30 minutes (while you roll out the bottom crust).

组装馅饼：

• 如果将面团冷藏几个小时或过夜，请坐在室温下直至柔韧，约20分钟。在略微面粉的表面上，将一个面团盘滚到一个直径12到13英寸的1/8英寸厚圆圈中，然后将其转移到9英寸的Pyrex Pie板上。将馅料倒入馅饼外壳中，然后用冷黄油将顶部倒在顶部。在一个小碗中，用1茶匙打蛋黄。水。用一些鸡蛋釉刷馅饼壳的边缘。

  Roll out the second dough disk as above and set it over the fruit filling to form a top crust. Press the edges of the dough together to seal the crust, trim the overhang to 1/2 inch, and fold it under. Flute or crimp the dough all around. Brush the top crust with the remaining egg glaze (you won’t need all of it). Cut four 1- to 1-1/2-inch-long steam vents in the top crust.

  Set the pie on a foil-lined rimmed baking sheet and bake until the pastry is golden brown and the fruit juices bubble thickly out of the pie, 70 to 80 minutes. Transfer to a rack and let cool completely before serving, about 4 hours.