Preheat the oven to 160°C (fan)/180°C/gas 4. Grease two 22cm round, sandwich tins and line with non-stick baking paper.
Break 250g chocolate into pieces and place in a heatproof bowl. Heat over a pan of gently simmering water until melted. Once the chocolate has melted completely, set aside to cool.
Put 3 eggs or chia eggs, 200g sugar and 100ml sunflower oil in a large mixing bowl and whisk together until smooth and creamy. Use an electric whisk if you have one.
Stir in the vanilla extract.
Sift over 100g self raising flour, 1/2 tsp bicarbonate of soda and 1/2 tsp baking powder. Gently fold into the mixture using a metal spoon. Fold in 50g ground almonds.
Next fold in 250g grated beetroot and the cooled chocolate until thoroughly mixed.
To make the buttercream beat the 100g butter or spread with 200g icing sugar. Gradually drizzle in the milk and beat some more until you have a spreadable consistency. Only add more milk if you think it's too dry.
Spread one cake with this buttercream and the other with the jam and sandwich together. Lightly dust with icing sugar and you're ready to go!
*To make 3 chia eggs add 3 tbsp ground chia seeds to a small bowl. Mix with 9 tbsp cold water and set aside until you have a gloopy paste. You can also use flax seeds (or lin seeds).