Method (cake)

1. Preheat your oven to 180ºC fan and line an 8 x 8 inch square cake tin with greaseproof paper. Allow the paper to hang over the tin slightly, this makes it easier to remove the cake when baked.
2. In a bowl, combine the dairy-free milk with the apple cider vinegar and whisk until fully combined. Set aside for 10 minutes to curdle. This creates a vegan ‘buttermilk’. Peel and mash up the bananas until soft, add into the milk and whisk to combine.
3. In a large mixing bowl, sift the sugar, flour, ground cinnamon, baking powder and bicarbonate of soda. Mix well to combine. Add the oil into the ‘buttermilk’ and whisk to combine.
4. Add the wet ingredients into the dry ingredients and mix just to combine.
5. Spoon half of the batter into the lined tin. Level it out with the back of a spoon or offset spatula.
6. Make the cinnamon sugar. In a small bowl, combine the light brown sugar and ground cinnamon until combined. Sprinkle the cinnamon sugar in an even layer over the batter. Pour the remaining batter over the cinnamon sugar, making sure to cover it (refer to video for example).
7. Place the cake into the middle of the preheated oven and bake for around 25-30 minutes. You will know it is done when you put a knife or skewer down the middle of the cake and it comes out clean and it’s springy to the touch. If batter comes off on the skewer, it needs more time to bake. To prevent burning, top the cake with some greaseproof paper then return back into the oven.
8. Allow the cake to cool in the tin for 10 minutes then carefully transfer onto a cooling rack. Allow to cool fully before frosting. You can even place the cake in a sealed container once cool then frost the day after. It’s a very light sponge so be careful with it when removing from the tin.

Method (cream cheese frosting)

1. In a stand mixer with balloon whisk attachment or in a bowl with an electric hand whisk, add in the soft butter and cold cream cheese, whisk on high speed for around 5 minutes – 8 minutes until pale and creamy. 
2. Gradually add in the icing / powdered sugar along with the vanilla. Whip until it’s thick and fluffy. If its too thick, add in some more chunks of cream cheese, too soft, add in more icing sugar to get it to the perfect creamy consistency. 
3. Spoon the frosting on top of the cold cake (make sure its fully cold as any heat from the cake will instantly melt the frosting). Spread out using an off set spatula or the back of a spoon. Make swirls in the frosting for the cinnamon sauce

Method (cinnamon sauce)

1. In a small saucepan, add in the butter and melt on the hob until melted.
2. In a small bowl, whisk together the melted butter, sugar, heavy cream and cinnamon until smooth.
3. Spoon the mixture into the swirls in the frosting, and use the back of a spoon or off-set spatula to gently swirl it around.
4. Cut the cake into squares using a sharp knife and serve. 
5. Serve the cake as is, or top with some vegan puff pastry cinnamon rolls and vanilla icing.