From 6 Bittersweets
Slightly adapted from Vegetarian Times
XIAOLU'S NOTES: I loved this combination of nuts, but feel free to substitute other nuts for 1 or all of the types in the recipe. Buy 1 orange for this recipe and you'll have more than enough zest and juice. If you don't have Greek yogurt, you can make a substitute from a cup of regular yogurt by draining it over a strainer lined with cheesecloth/paper towel/coffee filter for several hours. Make sure to measure the 1/2 cup for the recipe after you drain the yogurt. I always "make" my own brown sugar using white sugar and molasses, about 1 1/2 T molasses per cup of white sugar. That's one less ingredient in my overcrowded [as in, constantly on the verge of avalanche] pantry, and no problems with hardened old brown sugar.
1/4 cup each almonds, pecans, and hazelnuts
3/4 cup whole-wheat flour
1/4 cup sugar
1/4 tsp salt
6 T cold unsalted butter, diced
1 large egg yolk
Preheat oven to 350 degrees F. Coat 9-inch tart pan with cooking spray or a flavorless vegetable oil. Spread nuts on baking sheet, and toast in oven 12 to 15 minutes, or until browned.
Pulse nuts, flour, sugar, and salt in food processor until nuts are ground to powder. Add butter, and pulse until mixture resembles coarse meal. Add egg yolk, and pulse until moist clumps form.
Press dough into bottom and sides of prepared pan, about 1/4-inch thick, and pierce with fork. [If the dough is too soft to press, freeze it at 5 minute intervals until it's easier to handle. I pressed the dough with a floured juice glass.] Freeze crust for 30 minutes.
Adjust oven temperature to 400°F. Bake crust 12 to 14 minutes, or until golden. Let cool.
1/2 cup light or regular sour cream
1/2 cup plain Greek yogurt
2 to 3 T light brown sugar
1 tsp vanilla extract
1/4 tsp grated orange zest
1 1/2 to 2 cups blueberries
1 cup raspberries
1 T orange juice
Whisk together sour cream, yogurt, brown sugar, vanilla, and orange zest in small bowl. Toss berries with orange juice in separate bowl.
Spread sour cream mixture in crust with spatula. Spoon berries over top a little at a time, until sour cream mixture is evenly covered.
Refrigerate 30 to 60 minutes before serving.