Pre-heat the oven to 350°F, gas mark 4, 180°C (160°C fan-assisted).
Melt 200g chocolate together with either the coconut butter or coconut oil (odorless) stir until smooth and set aside.
In a large mixing bowl, beat the eggs by hand with a fork or whisk. Add the sweet white miso paste, vanilla bean paste or powder and sea salt. Pour the melted chocolate into the egg mixture together with the coconut sugar and mix until smooth. Then add the oat flour and continue to stir until thoroughly combined.
Using a 9x9 (23cm) square brownie tin, line with parchment paper and then pour the mixture in and scatter over the chocolate chips. Using the back of a spoon push chips into the mixture so they are not exposed.
Place in the pre-heated over for 25 minutes if you like them really fudge-style, 30 mins slightly firmer or 35 mins for cake-style brownies.
Leave to cool, then wrap in foil until required, I like to leave mine to rest for 24 hours so all the flavours develop.
To make the tahini miso chocolate sauce, add the agave nectar, sweet white miso, tahini, water, cacao and salt into a medium saucepan and stir until smooth, once mixed I use a spatula to flatten out any cocoa against the base of the sauce-pan, then gently heat over medium heat when ready to serve!