Fresh Berry Tart with Toasted Nut Crust

Source: Cooking Light (modified by Aimee)

Crust:
1/2 cup almonds
1/4 cup walnuts
3/4 cup whole wheat flour
1/4 cup sugar
6 TB chilled salted butter, diced
1 large egg yolk

Filling:
1 cup (8 oz) sour cream
1 cup plain Greek yogurt
1/4 cup light brown sugar
2 tsp vanilla
1/2 tsp grated lemon zest
1 cup blueberries
1 cup raspberries
2 tsp lemon juice

1. Crust: Preheat oven to 350. Spread nuts on baking sheet; toast in oven 12-15 minutes or until browned.
2. Pulse toasted nuts, flour, & sugar in food processor until nuts are ground to powder. Add butter & pulse until mixture resembles coarse meal. Add egg yolk & pulse until moist clumps form. Press dough into bottom & sides of oiled pie plate & pierce with fork. Freeze 30 minutes.
3. Adjust oven temp to 400. Bake crust 12-14 minutes; cool 1 hour.
4. Filling: whisk together sour cream, yogurt, brown sugar, vanilla, & zest in small bowl. Spread sour cream mixture in crust with spatula. Freeze 45 minutes. For best results, refrigerate overnight.
5. Toss berries with lemon juice in separate bowl; spoon over top & gently press into yogurt filling. Refrigerate until ready to serve.