Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch baking dish.
Stir together the sugar and vegetable oil in a large bowl until smooth. Beat in the eggs one at a time, then stir in the vanilla and sweet potatoes. Combine the flour, baking powder, baking soda, salt and cinnamon in a separate bowl; stir into the batter 1 cup at a time, alternating with the beer just until everything comes together. Spread the batter evenly in the prepared pan.
Bake for 35 minutes in the preheated oven, or until a knife inserted into the center of the cake comes out clean. Cool completely before frosting or serving.