Cream together the butter and sugar until soft and fluffy, then add the eggs one by one and mix in well.
130 g butter, 200 g caster sugar (superfine sugar), 2 large eggs
Mash the bananas and add them to the mixture along with the pumpkin puree and spices, and combine.
3 bananas, 150 g pumpkin puree, 2 tsp cinnamon, 1 tsp nutmeg, 1 tsp mixed spice
Fold in the flour plus the pinch of salt and combine carefully until mixed.
350 g self-raising flour, 1 pinch salt
Line the slow cooker pot with baking paper or a cake case.
Spoon the mixture into the lining paper/case and smooth the top.
Put the slow cooker lid on, with a tea towel folded under the lid to prevent drips from falling onto the cake mixture and making it damp.
Cook on high for 2-3 hours, or until a cake tester, skewer or knife put in the centre of the banana bread comes out clean. See Notes section for more tips!
Let the pot cool for a few minutes then remove the pumpkin banana bread from the pot by pulling the lining paper and leave to cool.
Serve warm or cold!