Preheat your oven to 180C/160C Fan and line a 9″ square baking tray with parchment paper.
Melt together the unsalted butter and dark chocolate in a heatproof bowl over a pan of boiling water, on the microwave for 1-2 minutes until melted. Leave to the side to cool to room temperature!
Using an electric whisk/stand mixer, whisk together the eggs & caster sugar for a few minutes until the colour has turned pale, is very mousse like, and is double the original volume of the amount of eggs + sugar!
You will know its done because when you lift the whisk up out of the mix it should leave a trail for a couple of seconds before disappearing!
When whisked, pour the cooled chocolate mix over eggs and fold together carefully. It might take some time, but be patient – you don’t want to knock out the air you made up on the previous step!
Once completely combined, sift the cocoa powder and plain flour on top of the chocolate mix and then fold together again – still be careful to not knock out the air!
Once combined well, fold through the chocolate chips and pour into the prepared tin – bake in the oven for 25-30 minutes! Once baked, leave to cool in the tin completely.
Notes
These triple chocolate brownies will last in an airtight container for 1 week!
If you find they're a bit hard to cut, stick them in the fridge for an hour and it'll make it a lot easier!
If they're not done in the time stated, then stick them in for longer, and cover with foil to prevent burning
They should be done when they're slightly wobbling when you shake the tin