2 medium red cooking apples, cored and very thinly sliced crosswise (see Tips)
2 tablespoons low-sugar orange marmalade
In a small bowl, combine oats, whole wheat flour, and ground pecans; set aside. In a large bowl, combine half of the cream cheese and the butter; beat with an electric mixer on medium to high speed for 30 seconds. Add brown sugar, orange peel, baking soda, and salt; beat until well mixed. Beat in as much of the oat mixture as you can with the mixer. Using a wooden spoon, stir in any remaining oat mixture. If necessary, cover and chill for 30 to 60 minutes or until easy to handle.
Preheat oven to 375°F. Pat dough evenly on the bottom and up the sides of a lightly greased 9-inch tart pan with a removable bottom. Line pastry with a double thickness of foil that has been coated with nonstick cooking spray. Bake for 4 minutes. Remove foil. Bake for 3 minutes more. Cool completely on a wire rack.
Meanwhile, in a medium bowl, combine the remaining cream cheese, the sour cream, egg white, 2 tablespoons orange marmalade, and ground cardamom; beat with an electric mixer until smooth. Spread into crust.
Arrange apple slices in two concentric rings atop the cream cheese mixture in tart pan, overlapping slices slightly. Cover top of tart with foil.
Bake for 35 minutes. Uncover and bake for 10 to 15 minutes more or until crust is golden brown and apples are just tender.
Place 2 tablespoons orange marmalade in a small microwave-safe bowl. Cover; microwave on 50 percent power (medium) for 10 seconds. Stir; microwave about 10 seconds more or until melted. Brush over apples. Serve tart slightly warm or cool.
Tips: We do not recommend using brown sugar substitute for this recipe.
If you have a mandoline, use it to slice the apples about ⅛ inch thick.
To toast nuts, spread in a shallow baking pan lined with parchment paper. Bake in a 350°F oven for 5 to 10 minu