Preheat the oven to 180°C. Grease and line a deep 20x30cm tin (if yours is very shallow, like mine, increase the height of the sides by using cut strips of cardboard from a cereal box or similar. Line the cardboard strips with baking paper).

In a large bowl, whisk together the flour, sugar, cocoa, salt, baking powder, and baking soda.

In a separate bowl, whisk together the eggs, milk, vanilla, oil, tahini and espresso or boiling water.

Whisk the wet ingredients into the dry ingredients until just combined.

Pour into the prepared tin and bake for 30-35 minutes or until a skewer inserted comes out with a few moist crumbs.

Set aside to cool.

Beat together the butter and tahini until creamy and combined. Gradually add the sifted icing sugar and beat to combine. Add the vanilla, salt and cinnamon.

If wanting the vanilla tahini icing: taste to adjust flavours. You’re done!

If wanting to make the half/half icing: remove half the icing at this point and set aside (just estimate). To the remaining icing, add 1/4 cup sifted cocoa and beat to combine.

If wanting just chocolate-tahini icing: add 1/2 cup sifted cocoa to the full icing at the stage where you beat in the sifted icing sugar, or at the end.