Gather all ingredients.

Preheat the oven to 350°F (175°C). Grease a sheet pan, then line it with parchment paper and grease the paper.

Beat eggs in a large bowl with an electric hand mixer until foamy. Add sugar, vegetable oil, and pumpkin purée; beat on medium speed until incorporated, about 2 minutes.

Mix flour, baking powder, cinnamon, baking soda, and salt together in a separate bowl. Beat flour mixture into egg mixture on low speed until just combined, about 1 minute. Pour batter into the prepared pan and spread out the edges.

Bake in the preheated oven until a toothpick inserted in the center comes out clean, about 25 minutes.

Cool completely, about 30 minutes.

Beat cream cheese, butter, and vanilla in a bowl with an electric mixer until creamy. Gradually mix in confectioners' sugar until smooth.

Spread frosting evenly over cooled cake layer, then sprinkle with cinnamon.