In a large mixing bowl, combine 1 1/4 cups all-purpose flour, 1/2 cup wheat flour, 1/4 cup sugar, and 1/4 tsp salt. Cut in 8 tbsp cold, cubed butter until the mixture resembles coarse crumbs.

In a separate bowl, mix 1 egg yolk and 1 tbsp of milk, then gradually add this to the flour mixture until a dough forms. Press the dough into a 9-inch pie pan, cover with plastic wrap, and refrigerate for at least 1 hour.

Preheat your oven to 400°F (200°C) and toss 12 oz of sliced rhubarb with 1/3 cup sugar, 1/2 tsp vanilla paste, 1/4 tsp cardamom, and 1/8 tsp ginger in a large baking dish. Cover with foil and bake for 20 minutes; then remove the foil and bake for an additional 5-10 minutes until the rhubarb is tender and slightly bubbling. Allow the rhubarb compote to cool to room temperature before using.

Once the crust has chilled, preheat your oven to 375°F (190°C). Line the chilled crust with parchment paper and fill with pie weights or dried beans. Blind bake for 10-12 minutes until the edges are lightly golden, then remove the weights and parchment, baking for an additional 3-5 minutes until the bottom is set and lightly golden.

In a blender or mixing bowl, combine 1/2 cup sugar, 1/4 cup yogurt, 3 eggs, zest from 1 lemon, and 2/3 cup freshly squeezed lemon juice. Blend until smooth and well combined.

Spread the cooled rhubarb compote evenly into the pre-baked crust. Carefully pour the prepared lemon filling over the top of the rhubarb. Bake in your preheated oven at 375°F (190°C) for 20-25 minutes, or until the filling is set but still has a slight jiggle in the center.

Allow the pie to cool at room temperature for 2-3 hours to let the custard firm up properly. Refrigerate the pie for at least 1 hour before serving, optionally topped with whipped cream.