Swedish Rhubarb Crumble with Vanilla Sauce

Why You’ll Love This Recipe

• Perfectly balanced: tart rhubarb under a buttery, oaty, golden crumble.
• Simple pantry ingredients with impressive results.
• Make the classic Swedish way: warm crumble, cold vanilla sauce.
• Easy to scale, easy to customize, and bakes in under an hour.

Grocery List

• Produce: Rhubarb (about 800 g), lemon (optional)
• Dairy: Unsalted butter, whole milk, heavy cream, eggs
• Pantry: Granulated sugar, light brown sugar, rolled oats, all-purpose flour, cornstarch, vanilla extract/paste, ground cinnamon (optional), fine salt

Full Ingredients

Rhubarb Filling

• 800 g rhubarb, trimmed and cut into 2 cm pieces (about 1.75 lb)
• 100 g granulated sugar (1/2 cup)
• 1.5 tbsp cornstarch (12 g)
• 1 tbsp fresh lemon juice (optional)
• 1 tsp finely grated lemon zest (optional)
• Pinch fine salt

Oaty Crumble Topping

• 90 g old-fashioned rolled oats (1 cup)
• 125 g all-purpose flour (1 cup, spooned and leveled)
• 80 g light brown sugar (1/3 cup, packed)
• 1/4 tsp fine salt
• 1/2 tsp ground cinnamon (optional)
• 113 g cold unsalted butter, cut into small cubes (1/2 cup, 1 stick)
• Optional finish: 2 tsp demerara or turbinado sugar to sprinkle on top

Vanilla Sauce (Vaniljsås)

• 300 ml whole milk (1 1/4 cups)
• 150 ml heavy cream (2/3 cup)
• 50 g granulated sugar (1/4 cup)
• 2 large egg yolks
• 1 tbsp cornstarch (10 g)
• 1 tsp vanilla bean paste or pure vanilla extract
• Pinch fine salt

Whipped Cream (Optional Alternative)

• 240 ml heavy cream (1 cup)
• 2 tbsp sugar (25 g)
• 1 tsp vanilla extract (optional)

Step-by-Step Instructions

Step 1: Heat the oven and prepare the dish

Preheat the oven to 190°C (375°F). Butter a 23 cm/9-inch round baking dish or similar 1.5–2 L casserole. Set the dish on a foil-lined baking sheet to catch any bubbling juices.

Step 2: Prep the rhubarb

Trim the leaves (toxic; discard) and any dry ends from the rhubarb. If stalks are very thick, peel away any tough strings. Cut into 2 cm pieces. In a bowl, toss rhubarb with granulated sugar, cornstarch, lemon juice and zest (if using), and a pinch of salt until evenly coated. Spread the mixture in an even layer in the prepared dish.

Step 3: Make the oaty crumble

In a medium bowl, combine oats, flour, brown sugar, salt, and cinnamon (if using). Add the cold diced butter. Using fingertips, a pastry blender, or two knives, cut the butter into the dry ingredients until you have moist crumbles with some pea- to marble-sized clumps. Do not overmix; visible oat and flour flecks are ideal.

Step 4: Assemble the crumble

Scatter the crumble evenly over the rhubarb, letting some small gaps remain so steam can escape. If you like extra crunch, sprinkle the top with demerara sugar.

Step 5: Bake until bubbling and golden

Bake for 38–42 minutes, rotating the dish halfway through. The top should be deep golden and crisp, and the rhubarb juices should bubble thickly around the edges. If the top browns too quickly, tent loosely with foil for the last 10 minutes. Let the crumble cool 10–15 minutes to set the juices.

Step 6: Make the vanilla sauce (vaniljsås)

While the crumble bakes, heat milk, cream, sugar, and a pinch of salt in a saucepan over medium until steaming. In a bowl, whisk yolks with cornstarch. Gradually whisk about 1/2 cup of the hot dairy into the yolks to temper, then pour the yolk mixture back into the saucepan. Cook over medium-low, stirring constantly with a spatula, until slightly thickened and 82–84°C (180–183°F), about 3–5 minutes; do not boil. Remove from heat, stir in vanilla, and strain into a jug. Cool to room temperature, then chill if you prefer it colder and thicker.

Step 7: Serve

Spoon the warm rhubarb crumble into bowls. Pour over cold vanilla sauce, or serve with softly whipped cream (whip cream with sugar and vanilla to soft peaks). Enjoy immediately for the best contrast of warm and cold.

Pro Tips

• For neat slices, let the baked crumble cool 20–30 minutes; juices thicken as it rests.
• If your rhubarb is very tart, add up to 20 g (1 1/2 tbsp) more sugar to the filling.
• Use cold butter and do not overwork the crumble; distinct clumps bake up extra crisp.
• Bake on a lined tray to catch drips and make cleanup easy.
• Vanilla sauce should never boil—keep it below a simmer for a silky, not curdled, finish.

Variations

• Strawberry-Rhubarb: Swap 250 g of rhubarb for hulled strawberries; reduce filling sugar to 80–90 g.
• Ginger Twist: Add 1 tbsp finely chopped candied ginger to the rhubarb and 1/2 tsp ground ginger to the crumble.
• Gluten- and Dairy-Free: Use certified gluten-free oats and a 1:1 gluten-free flour blend; replace butter with 115 g plant-based buttery stick. Serve with dairy-free vanilla custard or whipped coconut cream.

Storage & Make-Ahead

Store cooled crumble covered at room temperature for up to 1 day or in the refrigerator for 3–4 days. Reheat portions at 160°C (325°F) for 10–15 minutes to re-crisp the topping. The vanilla sauce keeps chilled for up to 3 days; whisk briefly before serving. To make ahead, assemble the crumble (unbaked), cover, and refrigerate up to 24 hours or freeze up to 2 months; bake from frozen, adding 10–15 minutes.

Nutrition (per serving)

Approximate values with vanilla sauce: 430 kcal; Fat 21 g; Carbohydrates 55 g; Sugar 31 g; Protein 5 g; Sodium 120 mg. Values will vary with ingredient brands and serving size.