Gradually add sugar to shortening, creaming until fluffy. Add egg, beat well. Add vanilla and milk. Sift together and add flour, baking powder and salt. Beat until smooth.
Bake in a 9 inch round layer pan or 8 inch square pan at 375 degrees for 20-25 min.
Remove from oven. At once spread with butter, than sprinkle with cinnamon and powder sugar over cake. Serve warm.