Step 1

1. Preheat the oven to 180°C (350°F/Gas 4). Grease a deep, 1.5 litre (52 fl oz/6 cup) baking dish.

Step 2

2. Bring a saucepan of water to the boil. Add the rhubarb and cook over high heat for 2 minutes, or until just tender. Drain well and place in a bowl.

Step 3

3. Add the blackberries, orange zest and 80 g (2 3/4 oz/ 1/3 cup) of the sugar and gently mix together. Taste and add a little more sugar if needed. Spoon the rhubarb mixture into the baking dish.

Step 4

4. In a bowl, mix together the flour, ground almonds, ginger and remaining sugar. Using your fingertips, rub the butter into the flour mixture until it resembles coarse breadcrumbs. Sprinkle the crumble mixture over the fruit, pressing down lightly, don't press it down too firmly, or the topping will become flat and dense.

Step 5

5. Place the dish on a baking tray and bake for 25-30 minutes, or until the crumble topping is golden and the fruit is bubbling underneath.

Step 6

6. Remove from the oven and leave to stand in the dish for 5 minutes. Serve warm, with cream or ice cream.