Preheat oven to 350 degrees. Spray a 9x13 baking dish with non-stick spray.
Whisk together the flour, baking powder, cinnamon, and salt in a large mixing bowl.
Add the sugar and eggs to a medium mixing bowl and beat with an electric mixer on medium speed for 3 minutes. Eggs should be thick, creamy, and pale yellow.
Add the oil, applesauce, and vanilla to the eggs and mix to combine.
Pour the liquid ingredients over the dry ingredients and mix well.
Add the apples and pecans to the batter and fold together.
Pour batter into prepared baking dish.
Combine the topping ingredients and sprinkle evenly over the cake batter.
Bake the cake for 50-60 minutes or until a tester comes out clean.
Cool completely before slicing and serving.