Beat the butter and sugar well for 5 minutes, add the milk and then flour gradually while stirring. Pour in the salt, baking powder, cinnamon and pour the prepared mixture into a pre-buttered and floured cake form.
Bake the cake in a moderately preheated oven initially on the lower element, and then on the upper and lower elements. Check its readiness with a toothpick.
Melt the butter for the glaze and mix it with the cocoa, sugar and 2 tablespoons of water. Top the finished cake with the glaze.