Method
Pumpkin Sheet Cake
Preheat oven to 350 degrees F
Grease a 9 x 13 baking dish.
Place melted butter, yogurt, eggs, brown sugar, granulated sugar, pumpkin puree, and vanilla extract in a mixing bowl.
Blend until smooth. Scraping the sides and bottom of the bowl.
Sift flour, baking powder, baking soda, salt, and pumpkin pie spice into the mixing bowl.
Blend with the wet ingredients until just combined., scraping the sides and bottom of the bowl.
Pour mixture into the greased 9 x 13 baking dish and bake for 30-35 minutes. Checking for overdoneness after 20 minutes.
If the cake is getting too brown, cover with a piece of foil.
When a toothpick comes out clean the cake is done.
Do not frost until the cake is completely cool.