Instructions

To make the rhubarb filling

1. Cook the rhubarb in a saucepan over medium-high heat with the sugar. The rhubarb will start to break down and release its own liquid.
2. Cook the rhubarb until it has softened and broken down, stirring frequently.
3. Taste the cooked rhubarb to see if you want to add more sugar.
4. Stir through the cornflour (cornstarch) to thicken the rhubarb mixture.
5. Take the saucepan off the heat.
6. Stir through the strawberries. The strawberries will start to soften from the heat of the cooked rhubarb.
7. Pour the cooked fruit into a large pie dish, about 23 cm or 9 inches wide.
8. Sprinkle over the raspberries.
9. Set the pie dish aside to cool slightly.

To make the crumble topping

1. Place the flour, salt and butter into a the bowl of a stand mixer with a flat-paddle attachment.
2. Beat on low speed until the butter starts to form large clumps with the flour, and the mixture resembles wet sand.
3. Alternatively, you can do this by hand by using your fingertips or a pastry blender to rub the butter into the flour, until you have a mixture which resembles wet sand.
4. Use a fork to stir through the sugars.
5. The crumble topping is ready to be used as is. However, if you like to have more crunchy bits in your crumble, you can use your fingertips to squeeze bits of the mixture together to form little clumps.

To assemble

1. Preheat the oven to 200°C/390°F (without fan).
2. Sprinkle the crumble topping over the rhubarb filling.
3. Bake for about 30 minutes or until the crumble is golden and the rhubarb filling is bubbling.