Preheat oven to 350 degrees F. Place oats in a large bowl. Pour the boiling water over oats; let stand for 10 minutes. Grease and flour a 13x9x2-inch baking pan; set aside.
Add granulated sugar, brown sugar, and butter to oats mixture; stir until butter is melted. Stir in eggs until combined. Stir in flour, baking soda, orange peel, and salt until combined. Stir in 1 cup of the butterscotch pieces.
Pour batter into the prepared pan. Sprinkle with pecans and the remaining butterscotch pieces. Bake in the preheated oven about 40 minutes or until a toothpick inserted near the center comes out clean. Cool completely in pan on a wire rack.