Make the strong tea - place 2 teabags in a small bowl, pour over 100ml boiling water and leave to cool and infuse for 5-10 minutes.
Remove the teabags, add the sultanas to the tea and leave to soak while you prep the rest of the ingredients.
Grease a 2lb (1kg) loaf tin with butter and line with baking paper or use a cake tin liner (no greasing required).
Pre-heat the oven to 170°C/340°F.
Add the softened butter, sugar and golden syrup to the mixing bowl and beat until soft and fluffy.
Add the ripe bananas and continue to beat (if the bananas are very ripe they won't need pre-mashing). Don't worry if the mixture looks a bit curdled at this point.
Weigh out the flour, cinnamon and mixed spice into a bowl.
Add one spoon of flour to the butter, sugar & banana mix along with one egg and gently beat until combined.
Repeat the previous step and add the 2nd egg and beat until combined.
Add the flour and spice mix to the mixing bowl along with the tea-infused sultanas and gently mix until the ingredients are all combined and you have a creamy looking batter.
Scrape the mixture into the lined loaf tin and bake for about 1 hour to 1 hour and 10 minutes or until a skewer comes out clean. (See below for tips on how to tell if the bread is cooked).