• Heat the oven to 350℉. Spray a 9x13 cake pan with nonstick cooking spray. Set aside.

Make The Cinnamon Streusel

• In a small mixing bowl, add the flour, light brown sugar, granulated sugar, and ground cinnamon. Whisk together until combined.
  1/2 cup all-purpose flour, 1/3 cup light brown sugar, 1/4 cup granulated sugar, ¼ teaspoon ground cinnamon
• Add in the cubed butter and use your clean fingers, or a pastry cutter, to mix together until the mixture resembles crumbled wet sand.
  4 tablespoons cold butter

Make The Pumpkin Cake

• In a large bowl, add the pure pumpkin, granulated sugar, oil, and large eggs. Use an electric hand mixer to beat until combined and smooth.

  ^{* You can also use a stand mixer with the paddle attachment if wanted.} 
  4 large eggs, 1⅔ cups granulated sugar, 1 cup canola or vegetable oil, 1 can (15 oz) pure pumpkin
• In a separate smaller bowl, whisk together the flour, baking powder, baking soda, cinnamon pumpkin pie spice, and salt.
  2 cups all-purpose flour, 2 teaspoons baking powder, 1 teaspoon baking soda, 1 teaspoon ground cinnamon, 1 teaspoon pumpkin pie spice, 1 teaspoon salt
• Add half of the dry ingredients into the wet ingredients and beat together just until combined. Add the other half and beat together just until combined and no flour streaks or pockets remain in the batter. 
• Pour the pumpkin batter into the prepared baking dish and sprinkle the cinnamon streusel over top.
• Cook for 30-38 minutes or until a toothpick inserted into the middle comes out clean or with tender crumb on it. The center of the cake should look set and the edges will be golden brown.
• Allow the cake to cool completely, on a wire rack, to room temperature before adding the glaze.

  ^{* You can also add the glaze to the cake when it's warm or closer to room temperature, it just depends on what temperature you want to serve the cake at. Warmed or room temperature. If the cake is warmer the glaze melts into the cake. For a glaze that stays on the cake (like what is pictured) add the glaze to the completely cooled cake.}

Make The Vanilla Glaze

• In a mixing bowl, beat together the butter and vanilla extract until creamy and smooth. Add the powdered sugar, cinnamon, and 1 tablespoon heavy cream and beat to combine. Keep adding heavy cream, in 1 tablespoon increments, until the desired consistency of glaze is achieved. 
  1 tablespoon butter, ¼ teaspoon vanilla extract, 1 cup powdered sugar, ¼ teaspoon ground cinnamon, 4 tablespoons heavy cream
• Drizzle the glaze over the cooled cake with a fork or place the glaze inside a ziplock bag and snip the corner off.