Upside Down Banana Cake Preparation time: 10 minutes Cooking time: 1 hour Serves: 10-12 INGREDIENTS 250g unsalted butter 180g dark brown sugar 2 tsp natural vanilla paste 4 ripe bananas, halved lengthways 250g caster sugar 3 eggs 2 egg yolks 125g self-raising flour 125g green banana flour 1 tsp baking powder 2 tsp ground cinnamon…