Brown butter, banana, tahini and chocolate cookies recipe

Ingredients

• 150 g unsalted butter
• 120 g plain (all-purpose) flour
• 120 g spelt flour
• 1 x ¾ tsp baking powder
• 0.5 tsp bicarbonate of soda (baking soda)
• 0.5 tsp fine sea salt
• 280 g dark chocolate (70% cocoa solids), roughly chopped, with some biggish chunks and some small bits
• 1 very ripe banana, about 100g/3½oz without skin
• 1 large egg
• 220 g soft light brown sugar
• 40 g granulated sugar
• 1 tsp vanilla extract
• 80 g tahini (must be smooth and runny enough to run off a spoon easily)
• 1 pinch sea salt flakes or fleur de sel, for sprinkling