Prepare the oven and tin – Preheat the oven to 180°C (350°F). Grease and line an 8-inch cake tin with baking paper.

Prepare the beetroot – Finely grate or puree the cooked beetroot until smooth. This ensures the cake has an even texture.

Mix wet ingredients – In a large bowl, whisk together eggs, caster sugar, vegetable oil, and vanilla extract until smooth.

Combine dry ingredients – In another bowl, sift together self-raising flour, cocoa powder, and baking powder.

Fold in beetroot – Add the grated beetroot to the wet mixture and stir gently until combined.

Add dry ingredients – Fold the flour mixture into the batter using a spatula. Mix until just combined.

Optional chocolate chips – Stir in dark chocolate chips for extra richness.

Bake the cake – Pour the batter into the prepared tin and bake for 35–40 minutes, until a skewer inserted into the center comes out clean.

Cool completely – Leave the cake to cool in the tin for 10 minutes, then transfer to a cooling rack.

Prepare frosting (optional) – Melt dark chocolate, beat butter and icing sugar, then mix in the chocolate and milk until smooth.

Finish the cake – Spread frosting over the cooled cake or simply dust with icing sugar.