Preheat your oven to 350°F (175°C). Grease a 9 by 13 inch baking dish thoroughly with butter or nonstick spray to ensure the cake doesn't stick to the pan.

In a large bowl, sift together the all-purpose flour, baking powder, kosher salt, baking soda, and pumpkin pie spice. This will help evenly distribute the leavening agents and spices throughout the flour for a uniform crumb.

In a separate medium bowl, whisk together the eggs, packed brown sugar, vegetable oil, canned pumpkin puree, 1 container (7 oz) Ellenos Limited Edition Pumpkin Pie Real Greek Yogurt (set aside the granola included in the yogurt for later), and vanilla extract until the mixture is well blended and smooth.

Add the wet ingredients from Step 3 into the bowl with the dry ingredients from Step 2. Whisk together until the batter is smooth, being careful not to overmix. If any streaks of flour remain, fold them gently into the batter with a rubber spatula.

Pour the batter from Step 4 into the prepared baking dish from Step 1. Use a spatula to spread it evenly. Bake in the preheated oven for about 35 minutes, or until a cake tester or toothpick inserted in the center comes out clean. I always test in a couple spots to be sure it's not underbaked in the middle!

Allow the cake to cool in the pan for about 15 minutes. Then, carefully invert it onto a wire cooling rack and let it cool completely until just barely warm. Once cooled, spread the remaining Ellenos Limited Edition Pumpkin Pie Real Greek Yogurt from the reserved container evenly over the top of the cake as a tangy frosting.

Sprinkle the reserved granola from the yogurt container evenly over the frosted cake for a crunchy finish. This adds great texture and extra pumpkin spice flavor! Slice and serve as desired.