Heat the oven to 190C/fan 170C/gas 5 and line a 20 x 30 rectangular baking tin with a wide strip of baking paper.
Put the dates, sultanas, butter, honey and a pinch of salt in a small pan and stir until melted. Simmer, stirring for 2 minutes until glossy. Add the almond butter and stir until melted in then add the oats and seeds and mix until fully incorporated.
Add the almond butter and stir until melted in then add the oats and seeds. Spoon the flapjack mixture into the tin and press downto level it out and compress (a potato masher is good for this). Bake in the oven for 18-20 minutes until golden.
Remove from the oven and leave to cool in the tin for 15 minutes before cutting into 12 squares (it’s easier to cut when a bit warm).Will keep in an airtight box or wrapped in baking paper and foil for 4-5 days.