Preheat oven to 180°C. line a 24cm×24cm square baking tray and grease with spray oil.
In a small sauce pan, melt butter. In a small bowl, mix together cocoa, sugar and salt then pour in butter and whisk to combine.
Whisk in the eggs and vanilla until well combined. Finally, ad flour and pecans and stir until just combined.
Pour into prepared pan and bake 25 minutes or until skewer inserted into the centre comes out clean. Allow to cool completely in the pan before slicing.