Luby's Butternut Brownie Pie

4 extra large egg whites (at room temperature)
1/8 teaspoon baking powder
1/8 teaspoon cream of tartar
1 1/4 cups granulated sugar, divided
14 graham cracker squares, broken into 1/2-inch pieces
1 cup pecan pieces
1 cup whipping cream
1/2 teaspoon vanilla extract

Heat oven to 300 degrees F. Place a small mixing bowl and beaters in the refrigerator to chill. Lightly grease a 9-inch pie plate.

In a large mixing bowl, beat egg whites and baking powder until soft peaks form. Add cream of tartar, beating constantly. Add 1 cup of the sugar, a tablespoon at a time, beating constantly until stiff peaks form. Using a rubber scraper, fold in graham cracker and pecan pieces. Spoon into prepared pie plate. Bake for 30 minutes or until a wooden pick inserted into center comes out clean. Cool completely on a wire rack.

In the chilled small bowl, beat whipping cream with chilled beaters just until it begins to thicken. Add remaining 1/4 cup sugar along with vanilla extract and continue beating until stiff peaks form. Do not over-beat. Top pie with whipped cream. Sprinkle with pecans and refrigerate until ready to serve.