Apple Blueberry Crisp with Oat Crumble

This apple blueberry crisp is everything a fruit crisp should be: a jammy, bubbling filling of tender apples and bursts of blueberry, all tucked under a golden, buttery oat crumble. It takes about 20 minutes to pull together, then the oven does the rest while you clean up or set the table.

I keep coming back to this version because the topping stays crisp without getting greasy, and the fruit filling thickens just enough that it doesn’t run all over the plate when you scoop it out.

Why This Crisp Always Works

The mix of apples and blueberries gives you the best of both worlds. The apples hold their shape and lend a hint of tartness, while the blueberries burst into pockets of deep sweetness. The oat topping has a high ratio of butter to flour, which means it bakes up shatteringly crisp rather than cakey.

I also love that you don’t need to precook the fruit. Just toss everything together, pile on the crumble, and bake. The cornstarch does its job in the oven, thickening the juices into a glossy sauce.

Ingredients

• 4 medium apples (about 1.5 lbs): peeled, cored, and sliced ¼ inch thick; Granny Smith or Honeycrisp both work well
• 2 cups blueberries: fresh or frozen, no need to thaw
• ¼ cup granulated sugar
• ¼ cup brown sugar: for the fruit filling
• 1 tbsp cornstarch: helps the filling set up
• 1 tbsp lemon juice
• 1 tsp ground cinnamon: plus more for the topping if you like
• ¼ tsp ground nutmeg: optional
• pinch of salt
• ¾ cup rolled oats
• ¾ cup all-purpose flour
• ½ cup unsalted butter, cold: cut into small cubes
• ¾ cup brown sugar: for the oat topping

Variations / Substitutions

• Swap pears for apples: pears bake softer, so add an extra teaspoon of cornstarch to keep the filling from getting watery
• Use all blueberries: double the berries and leave out the apples for a pure blueberry crisp
• Make it gluten-free: use a gluten-free all-purpose flour blend and certified gluten-free oats
• Go dairy-free: replace the butter with chilled coconut oil or a vegan butter stick

If you like this, you’ll probably enjoy my Peach Raspberry Crisp.

How to Make Apple Blueberry Crisp

Step 1: Toss the Fruit Filling

Heat your oven to 375°F (190°C). In a large bowl, toss together the 4 sliced apples, 2 cups blueberries, ¼ cup granulated sugar, ¼ cup brown sugar, 1 tbsp cornstarch, 1 tbsp lemon juice, 1 tsp cinnamon, ¼ tsp nutmeg if using, and a pinch of salt.

The mixture should look glossy and the cornstarch will start to dissolve. Don’t worry if the sugar hasn’t fully melted—that happens in the oven. If using frozen blueberries, the mixture might feel a bit firm, but it will bake up just fine.

Step 2: Work the Butter into the Crumble

In a separate bowl, combine the remaining ¾ cup brown sugar, ¾ cup rolled oats, ¾ cup all-purpose flour, ½ tsp cinnamon (or a little more), and a pinch of salt. Add the ½ cup cold, cubed butter and use your fingertips or a pastry blender to cut it in until the mixture looks like coarse crumbs with some pea-sized butter bits.

Those visible butter pieces are what create the crisp little clusters after baking. Try to work quickly so the butter doesn’t soften too much from your hands.

Step 3: Assemble and Bake

Pour the fruit filling into an 8-inch square baking dish (or a 9-inch pie plate) and spread it even. Sprinkle the oat topping in an even layer over the fruit, covering it completely.

The dish will look quite full, but the fruit will cook down and the topping will settle. Place the dish on a baking sheet to catch any juices that might bubble over. Bake for 45 to 50 minutes, until the fruit is bubbling thickly around the edges and the topping is deep golden brown.

Step 4: Spoon It Warm

Let the crisp cool on a wire rack for at least 15 minutes before scooping. This gives the filling a chance to set up so it doesn’t run when you serve it. Spoon generous portions into bowls and top with a scoop of vanilla ice cream or a pour of heavy cream.

The crumble will be crunchy and the fruit warm and jammy.

A Few Notes Before You Start

• Use firm-tart apples like Granny Smith, Honeycrisp, or Pink Lady so the slices keep their shape after baking. Softer apples can turn mushy.
• For a thicker crisp, add an extra teaspoon of cornstarch to the fruit mixture.
• Toasting the oats beforehand in a dry skillet for 3 to 4 minutes adds an extra nutty depth to the topping.
• You can assemble the crisp a few hours ahead of time. Keep it covered in the fridge, then bake it straight from cold, adding about 5 extra minutes to the bake time.
• Swap in ½ teaspoon of cardamom or ginger in the fruit for a slightly different warmth.

Bake times by pan size:

Storing Leftovers

• Refrigerate: Cover the cooled crisp tightly and store in the fridge for up to 3 days.
• Reheating: Warm individual portions in a 350°F oven for 10-15 minutes to recrisp the topping. A microwave also works, though the topping will soften.

What to Serve with Apple Blueberry Crisp

A scoop of vanilla ice cream is the classic move—the cold cream melting into the warm fruit and crisp topping. For something a little different, try a dollop of lightly sweetened mascarpone or a pour of cold heavy cream. A cup of black coffee or strong tea also cuts through the sweetness nicely.

Frequently Asked Questions

Can I use only apples instead of apples and blueberries?

Yes. Increase the apples to about 6 cups sliced and skip the blueberries. The bake time stays the same.

Why is my topping not crispy?

If the topping turns out soft, the butter may have warmed up before baking or you might have overmixed the crumble into a paste. Cold butter and minimal handling are key, plus baking at a hot enough temperature.

Do I need to peel the apples?

Peeling is recommended for the smoothest texture. The skin can become a bit chewy when baked, though some folks don’t mind it.

Can I use a different sweetener?

You can swap the sugars with coconut sugar or maple sugar. The flavor will shift a little, and the topping may be slightly less crisp, but it still works well.

Apple Blueberry Crisp Recipe

Print Recipe Pin Recipe

Prep Time 20 minutes mins

Cook Time 50 minutes mins

Total Time 1 hour hr 10 minutes mins

Servings: 6 servings

Calories: 490

Ingredients Method Notes

Ingredients

  

• 4 medium apples (about 1.5 lbs), peeled, cored, and sliced ¼ inch thick
• 2 cups blueberries, fresh or frozen
• ¼ cup granulated sugar
• ¼ cup brown sugar
• 1 tbsp cornstarch
• 1 tbsp lemon juice
• 1 tsp ground cinnamon
• ¼ tsp ground nutmeg (optional)
• pinch of salt
• ¾ cup rolled oats
• ¾ cup all-purpose flour
• ½ cup unsalted butter, cold, cubed
• ¾ cup brown sugar

Method

 

1. Heat oven to 375°F (190°C). Toss apples, blueberries, granulated sugar, ¼ cup brown sugar, cornstarch, lemon juice, cinnamon, nutmeg (if using), and salt in a large bowl.
2. In another bowl, combine ¾ cup brown sugar, oats, flour, cinnamon, and salt. Cut in cold butter with fingertips or a pastry blender until the mixture resembles coarse crumbs with small butter bits.
3. Pour fruit mixture into an 8-inch square baking dish (or 9-inch pie plate). Spread topping evenly over the fruit and place the dish on a baking sheet. Bake for 45-50 minutes until filling is bubbling thickly and topping is deep golden.
4. Cool on a wire rack for at least 15 minutes before serving. Spoon into bowls and top with ice cream or cream.

Notes

Cool for at least 15 minutes so the filling sets and doesn’t run. If using frozen blueberries, do not thaw; they may release a little more juice, so an extra teaspoon of cornstarch can help. The unbaked crisp can be assembled, covered, and refrigerated up to 4 hours; bake from cold, adding about 5 minutes.