Centre a rack in the oven and preheat oven to 160 degrees celsius / 325F.
Lightly grease with butter an 8" square tin / baking tray, line with baking paper / parchment paper.
Grease this with butter properly and keep aside.
In a large microwave safe bowl, place the chopped butter and microwave for 50 seconds to a minute until it's just melted.
Let this butter cool down for a bit, meanwhile get all the other ingredients.
In a small bowl, mix the flour, cinnamon powder, salt, coffee powder with a fork.
To the melted butter, add the cocoa powder and stir very well with a silicon / rubber spatula mixing them well together.
To this, add the eggs, one by one, mixing them well into the mixture. No need to beat and incorporate air into this. Mix in the sugar.
Add the vanilla extract and coffee liquor. Liquor is optional but it does take the taste to a whole new level. IIf you don't have coffee liquor add an extra table spoon of coffee powder.
Now, add the flour-cinnamon-salt-coffee mix to this and stir well for 2 minutes or so in a round motion to emulsify the mix well (so that butter doesn't ooze out after baking).
Final step is to add the nuts and chocolate bits. Fold them in and scrape the brownie batter into the parchment lined baking tin.
Bake for 25 minutes until the top appears papery.