4 stalks rhubarb
3 Braeburn apples
150g unsalted butter
1 tsp ground cinnamon
2 tbsp caster sugar
FOR THE CRUMBLE TOPPING
120g plain flour
60g caster sugar
60g unsalted butter at room temperature, cut into pieces
1. For the fruit filling, pull any tough strands of skin off the rhubarb - don't peel it completely or you won't have any colour left. Cut the stalks into fairly chunky pieces so they keep their shape and don't end up as a purée when you cook them. Peel and core the apples and cut them into similar sized chunks; we use equal quantities of each to balance the flavour.
2.Melt a knob of butter in a pan and sauté the fruit to drive off any extra water. If you don't do this now it will release a flood of liquid into the crumble and make it soggy. Add the cinnamon and sugar. Cooking the fruit right through at this stage means all you have to cook at the end are the crumble toppings, which is great if you are serving them at a dinner party, as you can finish them off in the oven during the main course.
3. Heat oven to 190C/170C fan/gas 5. Tip the flour and sugar into a large bowl. Add the butter, then rub into the flour using your fingertips to make a light breadcrumb texture. Do not overwork it or the crumble will become heavy.
4. Pour the fruit into baking dish and sprinkle the crumble mixture over the top. Don't pack it down, just let it take shape naturally. Bake for 40-45 minutes until nicely browned on top. I like to serve this crumble with custard. I haven't found a custart recipe so for now it's Ambrosia custard from a can.