Instructions:
Mix the dry ingredients together in a bowl. (If you don't have or don't want to use "pumpkin pie spice," just combine a mixture of your choice of allspice, nutmeg, clove, and/or ginger to your heart's content, but go light on the ginger if you use it.) Then add in the pumpkin, eggs, and juice, and stir that all together. Pour it into the pan, spread it evenly, and bake for only 15 minutes.
Sprinkle a damp linen towel with the two tablespoons of powdered sugar and turn the cake onto it. (Note: I used parchment paper for this and it was not damp, and mine turned out okay. I recommend trying it with a linen towel if you have one, but if you do, make sure it is not a textured one.) Roll the cake up lengthwise and let it cool on a rack for 20 minutes. Blend together the cream cheese, butter, vanilla, and cup of powdered sugar. (I recommend sifting the sugar before combining.) Unroll the cake when it is cooled properly and spread it all along the inside. Then roll the cake again without the towel. (You'll have some squeezing out. Concentrate the icing toward the inside when you spread it, because the outside is already going to have overflow from the squeeze. You will almost certainly have extra!)
Wrap the rolled cake in plastic and chill. When it's ready to serve, cut in slices.