preheat oven to 200·c

put parchment paper over a 20cm square pan or grease well and coat well with flour

put melted butter in a bowl and add cocoa powder, stir until smooth.

stir in sugar, salt, eggs one by one and cinnamon and stir well.

add flour and stir untill well combined

spread into pan

bake for 20 to 25 mins, knife should come out with some crumbels

let cool at least 10 mins then remove from pan