Preheat oven to 375 degrees F. Coat a 9-inch tart pan with a removable bottom with nonstick spray.
To make crust: Spread oats in another pie pan and bake, stirring occasionally, until toasted, 6 to 12 minutes. Let cool. Place the oats in a food processor and process until coarsely ground.
Stir together oats, flour, sugar, baking powder and salt in a large bowl. Drizzle oil onto dry ingredients and use a fork or your fingers to blend until crumbly. Using a fork, stir in water, 1 tablespoon at a time, until dough just comes together.
Turn the dough out onto a floured surface and knead 7 to 8 times. Roll the dough out to an 11-inch circle, dusting with flour if necessary. Transfer the dough to prepared pan, pressing to fit. Trim edges. (If necessary, use scraps to patch any holes in crust.)
To make filling & bake: Spread 1/2 cup pecans on a baking sheet and bake until fragrant, 5 to 10 minutes. Let cool and coarsely chop.
Whisk brown sugar, eggs, egg whites, corn syrup, vinegar, butter, vanilla and salt in a medium bowl until smooth. Stir in dried cranberries and the chopped pecans. Spoon filling into crust. Arrange remaining 1/2 cup pecans on top of the filling.
Bake the tart until filling is set and crust is golden, 20 to 25 minutes. Cool completely in the pan on a wire rack.
1/2 starch, 1 1/2 other carbohydrate, 2 fat