Preheat oven to 350°F (180°C). Line a 13×9-inch baking dish with parchment paper, letting excess extend over sides of pan.

For crust: In the bowl of a stand mixer fitted with the paddle attachment, whisk together flour, sugar, salt, and baking powder by hand. Add cold butter, and beat at medium speed until crumbly. Add egg, beating until combined and dough sticks together when pressed. Reserve 1 cup (130 grams) mixture in a small bowl; press remaining mixture into bottom of prepared pan.

Bake for 18 minutes. Leave oven on.

For filling: In a large heavy-bottomed saucepan, bring 3 cups (312 grams) cranberries, sugar, applesauce, orange zest, and salt to a boil over medium-high heat, stirring frequently until sugar dissolves. Reduce heat, and simmer, stirring occasionally, until cranberries begin to burst and mixture has thickened slightly, about 10 minutes.

In a small bowl, whisk together cornstarch and 1/ tablespoons (22.5 grams) water until smooth; stir into cranberry mixture. Cook until thickened, about 2 minutes. Remove from heat; stir in remaining 2 cups (208 grams) cranberries. Spread mixture in an even layer onto prepared crust. Sprinkle reserved 1 cup flour mixture and pecans onto cranberry mixture.

Bake until crust is golden brown and filling is bubbly, 30 to 45 minutes. Let cool completely in pan on a wire rack. Refrigerate until firm, about 1 hour, or freeze for 15 minutes.

Using excess parchment as handles, remove from pan, and cut into bars. Store in an airtight container for up to 4 days.