Preheat your oven to 180°C (350°F).

Line a baking tray (approximately 20cm x 20cm) with parchment paper.

In a mixing bowl, combine the chopped dark chocolate and cubed butter. Melt them together in a microwave or over a bowl of hot water. Stir until smooth and set aside to cool slightly.

In another bowl, whisk together the eggs and soft brown sugar until they become light and fluffy.

Once the chocolate and butter mixture has cooled, pour it into the egg mixture and stir gently until combined.

Add the grated beetroot into the mixture and mix well.

In a separate bowl, sift together the plain flour, cocoa powder, baking powder, and salt.

Gradually fold the dry ingredient mixture into the wet mixture, being careful not to overmix.

Transfer the brownie batter into the prepared baking tray, spreading it evenly using a spatula.

Place the tray in the oven and bake for about 25-30 minutes, checking for doneness with a toothpick.

Once baked, cool in the tray for about 10 minutes, then lift out using the parchment paper and cool completely on a wire rack.