Peach and Blackberry Tart with Oatmeal Cookie Crust

A few years ago I took a baking class. This was one of my favorite recipies that we got. It's really not that hard to make.

CRUST:
Non-stick vegetable oil spray
2 C. oatmeal cookie crumbs
5 tbsp. unsalted butter, melted

FILLING:
2/3 C. peach or apricot nectar
5 tbsp. sugar
5 tsp. cornstarch
2 2/3 C. coarsely chopped, peeled peaches
1 1/4 tsp. fresh lemon juice
½ pt. large blackberries

CRUST: Preheat the oven to 375°. Spray a 10-inch diameter fluted tart pan with non-stick spray. Mix the cookie crumbs and melted butter in a medium bowl until moist clumps form. Press the dough evenly over the bottom and up the sides of the prepared pan. Bake until dry, about 10 min. Cool crust completely.

FILLING: Whisk the nectar, sugar, and cornstarch in a heavy saucepan until smooth. Add half of the peaches and the lemon juice. Using a potato masher, mash to a coarse puree. Simmer over medium heat until the mixture is thick, stirring constantly, about 5 min. Cool completely. Fold in the remaining peaches. Spread the filling evenly in the crust. Arrange the blackberries around the top edge of the tart. Refrigerate until cold, at least two hours and up to six hours. Bring to room temperature before serving.