Ingredients:

  • 5 cups fresh rhubarb, sliced into 1/2 inch pieces
  • 3/4 cup granulated sugar
  • 2 tbsp cornstarch
  • 1 tsp ground cinnamon
  • 1 tbsp lemon juice
  • 1 cup all-purpose flour
  • 1 cup rolled oats
  • 1 cup packed light brown sugar
  • 1/2 tsp salt
  • 1/2 cup unsalted butter, cold and cubed

Instructions:

  1. Preheat the oven to 375°F (190°C).
  2. In a 9x13 inch baking dish, combine the sliced rhubarb, granulated sugar, cornstarch, cinnamon, and lemon juice. Toss gently until the rhubarb is evenly coated and the sugar has begun to dissolve. Spread into an even layer.
  3. In a medium bowl, whisk together the all-purpose flour, rolled oats, light brown sugar, and salt.
  4. Add the cold, cubed butter to the flour mixture. Use a pastry blender or fingertips to work the butter in until the mixture resembles coarse crumbs with some pea-sized lumps remaining.
  5. Scatter the crumble topping evenly over the rhubarb base, pressing down very lightly with your palm.
  6. Bake for 30–35 minutes until the fruit juices are bubbling around the edges and the topping is deep golden-brown.