Heat your oven to 160c/325f/GM3.
Put the protein powder, cacao powder, buckwheat flour and cinnamon into a large bowl. Mix well.
Put the pitted dates into a jug with the plant milk. Blend the dates and milk with a hand blender, pour this into the bowl and mix in.
Line a brownie pan or baking tray with baking paper. Pour in the brownie batter. Bake for 15-25 minutes until the brownies are firm on top but still slightly squidgy underneath.
Allow the brownies to cool then chill in the fridge before cutting. Cut the brownies into 16 pieces.
Toppings - Mix the peanut butter and coconut oil together in a small bowl. Pour it onto 4 brownies then add coconut chips. Mix the cacao powder, water and coconut oil together in a small bowl. Pour it onto the remaining 12 brownies. Add cacao nibs and pecans to four brownies, fennel seeds and lemon to 4 brownies and chilli flakes to the remaining 4 brownies.
Put the brownies into Tupperware boxes in a single layer and put into the freezer.