• Preheat the oven to 350 degrees and line a 9x13-inch baking pan with parchment paper and non-stick spray.

Pumpkin Cake

• In a medium-sized bowl, whisk together the flour, pumpkin pie spice, ground cinnamon, baking powder, salt, and baking soda. Set aside.
• In a large bowl, whisk together the brown sugar, sugar, pumpkin puree, olive oil, eggs, and vanilla extract until fully combined.
• Alternate adding the flour mixture and the kefir milk to the wet ingredients (flour, milk, flour), whisking just until everything is combined (be careful not to overmix).
• Pour the batter into the prepared 9x13-inch pan and smooth it out into an even layer using an offset spatula. Bake for 25-30 minutes, or until a toothpick inserted into the middle comes out clean. Cool completely.

Maple Frosting

• In the bowl of an electric stand mixer using the paddle attachment, beat the butter on high speed until light and creamy (1-2 minutes).
• Add the powdered sugar, maple syrup, and maple extract and mix on low speed until combined. Then increase the speed to high and beat for another 1-2 minutes (frosting should be light and creamy).

Decorate

• Once the cake has completely cooled, remove it from the pan with the parchment paper handles. Spread on the maple frosting using an offset spatula. Slice the cake into 18 pieces and serve.
• Keep any leftover cake pieces in an airtight container at room temperature for 2 days or in the refrigerator for up to 5 days.