1. Preheat oven to 350°F (177°C). Grease a 9×13-inch baking pan and line with parchment paper.
2. In a bowl, combine flour, baking powder, baking soda, salt, cinnamon, and pumpkin pie spice.
3. In another bowl, whisk oil, eggs, brown sugar, sugar, pumpkin puree, and vanilla.
4. Stir wet and dry ingredients until the batter is smooth.
5. Pour batter into the pan. Bake for 30-40 mins until a toothpick comes out clean.
6. Cool cake in the pan on a rack. Refrigerate for faster cooling (about 2 hours).
7. Beat cream cheese and butter on medium speed until creamy for frosting.
8. Gradually add powdered sugar, beating until light and fluffy. Add vanilla and salt.
9. Spread frosting over the cooled cake. Drizzle with maple syrup and pecans, if desired.
10. Chill cake for 30 mins before slicing to set frosting.