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Serving a slice of Mixed Berry Plum Pie

Triple Berry Plum Pie Recipe

  • Author: Rebecca Blackwell
  • Prep Time: 60 minutes (plus 3 hours to let the fruit drain)
  • Cook Time: 1 hour
  • Total Time: 2 hours (plus 3 hours to let the fruit drain)
  • Yield: 8 slices


 This mixed berry and plum pie has a perfectly balanced sweet-tart filling made with raspberries, blackberries, blueberries and plums inside a flaky, sugar coated lattice topped pastry. I can't think of a better way to take advantage of fresh berry season. 


  • 1 recipe Fool Proof Pie Crust, chilled for at least 30 minutes in the refrigerator
  • 6 heaping cups fresh berries, any mix of varieties (for the pie pictured, I used raspberries, blueberries, and blackberries)
  • 6 small black plums, unpeeled, pitted and cut into 1/2-inch slices
  • 1/4 cup lemon juice
  • ¾ cup + 2 tbsp granulated sugar, divided (plus more for sprinkling over the top crust)
  • 1/4 c quick cooking tapioca
  • 3 tbsp cornstarch
  • 1 tsp salt
  • ¼ cup honey
  • 1 tbsp lemon zest
  • 1 tsp pure vanilla extract
  • 1/2 cup good quality fruit jam or preserves (Optional. *See note)
  • 1 large egg


  1. Wash the berries in cold water and let drain. Put them into a large bowl with the sliced plums and very gently toss the fruit with 1/2 cup of the sugar and the lemon juice. Pour the fruit into a colander and set the colander over the bowl so that it catches all the juice. Let sit for 3 hours. If you think about it, gently stir the fruit in the colander every now and then to encourage as much juice as possible to drip down into the bowl. (If you forget, or are unable to stir the fruit, don't worry about it. It'll be fine.)
  2. Preheat the oven to 400.
  3. Remove the colander with the fruit in it from the bowl and pour the fruit juice that's collected in the bowl into a medium size saucepan. Dump the fruit into the bowl and set aside.
  4. Using a spice grinder or food processor, grind the tapioca into a powder. (*See note) Add the ground tapioca, remaining sugar, cornstarch, salt, honey, and lemon zest to the fruit juice in the saucepan. Whisk vigorously to combine and set it over medium-high heat.
  5. Cook the fruit juice mixture, stirring constantly, until the mixture comes to a boil. Boil, stirring constantly, for 5 minutes, until it's thickened to the consistency of gravy. (*See note) Remove from the heat and stir in the vanilla.
  6. Pour the fruit juice mixture over the fruit. Toss gently to combine and set aside while you roll out the pie crust.
  7. Remove the pie dough from the refrigerator. On a floured surface, roll out a portion of the dough to a 12-inch circle that’s about ⅛-inch thick. Using a large spatula, gently loosen the dough from the work top, fold it in half and then fold it in half again. It will form a triangle shape. Lift the crust and place it in a pie plate with the point of the triangle in the center of the plate. Gently unfold the dough in the pan and press into the corners gently. Leave any dough that overlaps the edges of the plate in place.
  8. OPTIONAL (*See note): Spread 1/2 cup of fruit jam or preserves in an even layer over the bottom of the pie crust.
  9. Roll another portion of the dough into a large circle, about 18 inches. With a pizza wheel, fluted pizza wheel, or paring knife, cut the disk into 1 or 2-inch wide strips.
  10. Pour the fruit filling into the bottom crust, smoothing it into an even layer.
  11. Starting in the center of the pie, lay half the strips across the top of the filling in one direction. Lay the remaining strips perpendicular to the first, weaving them into the first strips to form a lattice pattern. Trim the edges of the strips so that they are even with the edge of the bottom crust.
  12. Fold the edges under, forming a rim around the pie that is a bit higher than the pie plate. With one hand on the inside of the edge and one hand on the outside, use the index finger of your inside hand to push the dough between the thumb and index finger of your other hand to form a U or a V shape. Continue this crimping motion around the entire edge.
  13. In a small bowl, whisk the egg with 1 tbsp of cold water. Gently brush the egg wash over the top crust with a pastry brush and sprinkle evenly with 2-3 tablespoons of sugar.
  14. Put the pie on a foil covered baking sheet and place in the oven. (To catch the drips. *See note) Bake for 30 minutes. Reduce the oven temperature to 375 and bake for an additional 30-40 minutes. The pie is done when the crust is a deep golden brown and the filling in the center of the pie is bubbling.
  15. Remove from the oven and cool completely on a wire rack, about 4-6 hours, before slicing.


  • Spreading the bottom crust with jam is optional, but delicious. If you didn’t know that it was in there, I don’t think you could pick it out. But if you taste two slices of this pie back-to-back, one with jam and one without, you WILL notice that the pie with jam has a bit more fruity flavor. My favorite kind of jam to use is Morello Cherry Preserves because it’s rich, tart and incredibly flavorful.
  • The bowl of my food processor is kind of large, so I find it easier to grind a larger amount of tapioca at once. Store ground tapioca in a zip top bag in the cupboard, just as you would unground tapioca.
  • The amount of juice you get from your berries will vary, so after boiling the fruit juice with cornstarch and tapioca for a few minutes, if your juice isn't thickening to the constancy of gravy, you might need to add a bit more cornstarch. Sprinkle in another teaspoon or two, cook for a few seconds longer, and see if that does the trick. If not, add a touch more.
  • Placing the pie on a foiled covered baking sheet is super important because most of the time, some of the filling will bubble up and drip over the sides of the pie plate. The foil covered baking sheet will catch these drips, saving you from an oven of burning fruit. Covering the baking sheet with foil (or parchment paper), makes clean up super easy. Just be sure to remove the pie from the baking sheet right after baking or the foil (or parchment) will stick to the pie plate as it cools and be somewhat difficult to remove.