Preheat oven to 350°F (180°C).

Fit the pie crust into a 9-inch pie plate; line crust with parchment paper and fill with dried beans or pie weights.  Bake until crust is lightly browned, about 35 minutes.  Lift and remove parchment paper and pie weights and let crust cool.

While pie crust is cooling, prepare filling.  Combine water and chickpeas in a blender and process until smooth.  Combine with the frozen berries, lemon zest and juice in a medium saucepot.  Set aside.

In a medium bowl, combine sugar, corn starch, cinnamon and salt together with a whisk.  Stir into the berry-chickpeas mixture.  Cook on medium heat until the mixture thickens and starchy taste from corn starch is gone, about 5-7 minutes.  Pour filling into prepared pie pastry, spread out evenly and chill in fridge uncovered for 2 hours or overnight.

Preheat oven to 350°F (180°C).

For the aqua faba meringue: combine the reserved chickpea liquid and cream of tartar in a stand mixer with whisk attachment.  Whip on high setting until soft peaks form.  Add sugar and continue to whip on high until stiff peaks form.  Spoon the meringue over the prepared pie, spreading it out all the way to the edges.  Use a spatula, knife or fork to make designs of your choice.

Bake the pie for 8-12 minutes until golden, while checking in on it often as the peaks can burn quickly.

Chill fully in the fridge uncovered for 2 hours, or cut pie immediately and enjoy!

TIPS

• Fun fact, you cannot over whip aqua faba!  Whip a little longer if you are concerned the peaks are not fully developed.
• For a stronger meringue, reduce 3/4 cup (175 mL) of aqua faba to 1/2 cup (125 mL) by simmering via stovetop, reducing the liquid through evaporation.  Chill and whip up as directed in the aqua faba meringue step.  This will provide a denser meringue, less likely to separate if left chilling overnight.