Rhubarb Crisp (Old-Fashioned, Easy, and Perfectly Sweet-Tart)
This classic Rhubarb Crisp layers a bubbling, sweet-tart rhubarb filling under a buttery, crispy oat crumble topping. It’s simple, nostalgic, and perfect for spring gatherings, Sunday dinners, or an easy weeknight dessert.
Ingredients
- 6 cups rhubarb about 1 1/2 pounds, fresh or frozen, chopped into 1/2–3/4-inch pieces
- 1 cup granulated sugar for the filling; reduce to 3/4 cup for a more tart dessert
- 3 tablespoons cornstarch helps thicken the juices
- 1/4 teaspoon fine sea salt for the filling
- 1 teaspoon pure vanilla extract
- 1 tablespoon fresh lemon juice
- 1 1/2 cups old-fashioned rolled oats not quick oats
- 1 cup all-purpose flour
- 3/4 cup light brown sugar packed, for the topping
- 1/2 cup granulated sugar for the topping
- 1 teaspoon ground cinnamon
- 1/4 teaspoon ground nutmeg optional, for the topping
- 1/2 teaspoon fine sea salt for the topping
- 1 cup unsalted butter 2 sticks, cold, cut into small cubes
Instructions
- Preheat your oven to 375°F (190°C). Lightly butter or spray a 9x13-inch baking dish. A glass or ceramic dish works best for even baking.
- Wash the rhubarb stalks well and pat dry. Trim off and discard the leaves and any dry ends. Slice the stalks into 1/2–3/4-inch pieces so they cook evenly.
- In a large bowl, combine the chopped rhubarb, 1 cup granulated sugar, 3 tablespoons cornstarch, 1/4 teaspoon fine sea salt, vanilla, and lemon juice. Toss until the rhubarb is evenly coated and no dry cornstarch remains.6 cups rhubarb, 1 cup granulated sugar, 3 tablespoons cornstarch, 1/4 teaspoon fine sea salt, 1 teaspoon pure vanilla extract, 1 tablespoon fresh lemon juice
- Pour the rhubarb mixture into the prepared baking dish and spread into an even layer, making sure the cornstarch-sugar mixture is evenly distributed.
- In another large bowl, stir together the oats, flour, brown sugar, 1/2 cup granulated sugar, cinnamon, nutmeg (if using), and 1/2 teaspoon fine sea salt. Add the cold butter cubes and cut them into the dry ingredients with a pastry cutter, two forks, or your fingertips until you have pea-sized crumbs and clumps.1 1/2 cups old-fashioned rolled oats, 1 cup all-purpose flour, 3/4 cup light brown sugar, 1/2 cup granulated sugar, 1 teaspoon ground cinnamon, 1/4 teaspoon ground nutmeg, 1/2 teaspoon fine sea salt, 1 cup unsalted butter
- Sprinkle the oat crumble evenly over the rhubarb filling. Do not press it down; keep it light and fluffy so it crisps well. Cover the surface and reach into the corners so every bite has topping.
- Bake on the center rack for 35–45 minutes, or until the rhubarb filling is bubbling around the edges and in a few spots in the center, and the topping is deep golden brown. If the topping browns too quickly, loosely tent with foil during the last 10 minutes.
- Transfer the pan to a cooling rack and let the rhubarb crisp rest for 15–20 minutes. This allows the juices to thicken so the servings hold together better.
- Spoon the warm rhubarb crisp into bowls and serve plain or topped with vanilla ice cream, whipped cream, or a spoonful of Greek yogurt.
Notes
Use fresh or frozen rhubarb; if frozen, thaw fully and drain off excess liquid before measuring. Adjust the sugar to taste—use the full amount for a sweeter dessert or reduce for a more tart crisp. Do not overwork the topping; stop mixing when you see pea-sized crumbs for the best crumbly texture. Bake until you see active bubbling in the filling for a properly thickened crisp. Leftovers keep well and can be reheated in a 350°F oven for 15–20 minutes to re-crisp the topping.