Note: If you want a more pronounced hānati (hazelnut) flavour in this keke (cake), toast the hānati (hazelnuts) before making the batter. Add the whole nuts in to a dry frying pan and over medium heat, toast the nuts until fragrant. Once they are toasted, add them to a tea towel and rub off the skins. Allow them to cool as you make the cake batter.
Preheat the oven to 150 °C.Grease and line 2 x 19 cm or 20 cm cake tins with baking paper on the base and sides. Combine the miraka (milk) and winika (vinegar) in a glass. Stir to create a simple buttermilk. Leave to the side.
To a jug or medium bowl, add the kōkō (cocoa), huka hāura (brown sugar), tote (salt) and paura kawhe (coffee powder). Mix it up.
Boil the jug and pour the wai wera (hot water) in to the cocoa mix. Stir it. Once the ranunga kōkō (cocoa mixture) is smooth and free of lumps, pour in the miraka pata (buttermilk) and stir it in. Leave to the side. In to a large bowl, add the hēki (eggs), huka one (caster sugar) and wanira (vanilla). Using a whisk, whip for a minute or so until smooth.
Slowly drizzle in the noni (oil) as you whisk it in to a smooth batter. Continue whisking as you pour in the cocoa mixture. Add the hānati (hazelnuts) in to a blender and turn them in to a crumb, be careful not to take them too far as they will start to turn in to hazelnut butter. Just pulse until a crumb forms. Reference the video for a visual cue.
Add the kongakonga hānati (hazelnut crumb) in to the main mixture along with puehu parāoa kore-wīti (gluten-free flour mix), pēkana paura (baking powder) and pēkana houra (baking soda).Whisk it all together for a minute or so until the batter is smooth. Divide it evenly between the two prepared cake tins.
Bake for 35 minutes or until they spring back in the centre when pressed.
Remove the cakes from the oven. Flip them straight on to a cooling rack as this helps them stay flat so you don't have to trim the cakes. Leave the baking paper on the cakes until you are ready to decorate them.Allow them to completely cool before decorating.