1. Preheat your oven to 180C/Fan 160C/Gas 4. Use the back of a spoon to crack open the cardamom pods and shake the seeds out into a pestle and mortar. Grind into a fine powder. No pestle and mortar? Use a small, sturdy bowl and the end of a rolling pin or base of a jam jar instead.
2. Peel the pears, quarter them and scoop out the seeds and cores. Melt 50g of the butter in a frying pan. Add the pears, ground cardamom and 50g of the sugar. Sizzle, gently stirring often to turn the pears, for 8-10 mins till the pears are lightly browned and softened. Tip the pears and their pan jucies into an ovenproof dish.
3. Roughly chop the chocolate buttons and scatter them over the pears. Set aside.
4. Chop the remaining 100g cold butter into a mixing bowl. Shake in the sprouted porridge oats, flour and the remaining 25g caster sugar. Add a pinch of salt. Use your fingertips to rub everything together to make small, soft clumps. This wil take 3-4 mins.
5. Sprinkle the crumble topping over the pears to cover them. Slide the tin into the oven and bake for 30-40 mins till golden and bubbling. Let the crumble cool in the dish for 10-15 mins, then serve with double cream or custard.