Ingredients:
- 5 cups (600g) fresh rhubarb, chopped into 1-inch pieces
- 3/4 cup (150g) granulated sugar
- 2 tbsp (20g) tapioca starch or cornstarch
- 1 tbsp (15ml) lemon juice
- 1 tsp (2g) lemon zest
- 1/2 cup (115g) unsalted butter, cold and cubed
- 3/4 cup (150g) brown sugar, packed
- 1 cup (125g) all-purpose flour
- 1 cup (90g) rolled oats
- 1 tsp (2g) ground cinnamon
- 1/4 tsp (1.5g) salt
Instructions:
- Toss the chopped rhubarb, granulated sugar, tapioca, lemon juice, and zest in a medium bowl. Stir until the rhubarb is evenly coated and the starch is dissolved.
- Transfer the rhubarb mixture into a 9x9 inch baking dish, spreading it into an even layer.
- Place the flour, brown sugar, cinnamon, and salt in the food processor bowl and pulse 2-3 times to combine.
- Add the cold, cubed butter. Pulse in 1-second bursts until the mixture resembles small peas and begins to clump.
- Add the rolled oats and pulse just 2-3 more times until just combined; do not overprocess.
- Spoon the crumble mixture over the rhubarb, scattering it evenly without pressing it down.
- Bake at 375°F (190°C) for 45-50 minutes until the fruit juices bubble around the edges and the topping reaches a deep, mahogany-brown hue.