Remove from the heat. Add the vanilla and cider vinegar and stir.
1 tsp apple cider vinegar, ½ tsp vanilla extract
Sift in the dry ingredients and gently stir, adding the water bit by bit as you go along.
100 g wholemeal spelt flour, ¾ tsp baking powder, ⅛ tsp bicarbonate of soda (baking soda), 25 g cocoa powder, 75 ml hot water
Line or oil the cake pan (or use a 15cm / 6" silicone mould or tin).
Pre-warm the air-fryer as instructed.
Scrape the batter into the pan and cover with foil.
Set the temperature to 170℃ (340℉) and bake for 25 minutes. Remove the foil, set the timer for a further 10 minutes and bake until an inserted skewer comes out more or less clean. Alternatively bake in the middle of an oven at 180℃ (350℉, Gas 4) following the same procedure as above, but for an extra 10 to 15 minutes.
Remove the pan and allow to cool for ten minutes before turning out onto a wire rack to cool completely.
Chocolate Cashew Icing
Melt the coconut oil in a pan over very low heat. Add all the other ingredients, except for the chocolate and stir until smooth.
10 g coconut oil, 1 tbsp cashew nut butter, 1 tbsp maple syrup*, ¼ tsp vanilla extract, pinch Himalayan pink rock salt
Remove from the heat - add the chocolate and stir until combined.
25 g dark chocolate
Spread over the top of the cake.
Scatter with dark chocolate shavings if wished.
Notes
The cake is quite rich, so a little goes a long way.Double the quantities for a 20cm / 8" cake tin and bake for an additional 10 to 15 minutes.Can bake in a conventional oven at 180℃ (350℉, Gas 4).Please note: calories and other nutritional information are per serving. They're approximate and will depend on exact ingredients used.