Raspberry Oatmeal Crumble Bars

Name: Raspberry Oatmeal Crumble Bars
Prep time: 30 min
Cook time: 47 min
Total time: 1 h 17 min
Yield: 16 servings
Cuisine: American
Ingredients: 1½ cups (190 g) all-purpose flour, spooned into the cup and leveled; 1½ cups (135 g) old-fashioned rolled oats; ¾ cup (150 g) light brown sugar, firmly packed, any lumps broken up; ½ teaspoon (2½ g) baking soda; ½ teaspoon (3 g) fine sea salt; ½ teaspoon (1½ g) ground cinnamon; 12 tablespoons (1½ sticks) (170 g) unsalted butter, melted and cooled for about 5 minutes, plus a little extra, softened, for greasing the pan; 1 teaspoon (5 ml) pure vanilla extract; 1 cup (12 oz jar) (340 g) seedless or seeded raspberry jam, thick and spreadable; 2 teaspoons (6 g) cornstarch; 1 tablespoon (15 ml) fresh lemon juice; 1 teaspoon (2 g) lemon zest, finely grated; 1 cup (125 g) fresh raspberries, rinsed, patted completely dry (whole berries) (optional)

From the MyKitchenBank Kitchen

A buttery brown sugar oat crust and crumb topping sandwich a layer of tangy raspberry jam brightened with lemon. Simple, sturdy, and easy to slice for lunchboxes, picnics, or dessert.

Prep: 30 min
Cook: 47 min
Wait: 2 hr
Total: 3 hr 17 min
Makes: 16 bars (one 9×9-inch pan)

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Ingredients

16 servings

For the oat crust and crumble
1½ cups (190 g) all-purpose flour, spooned into the cup and leveled
1½ cups (135 g) old-fashioned rolled oats
¾ cup (150 g) light brown sugar, firmly packed, any lumps broken up
½ teaspoon (2.5 g) baking soda
½ teaspoon (3 g) fine sea salt
½ teaspoon (1.5 g) ground cinnamon
12 tablespoons (1½ sticks) (170 g) unsalted butter, melted and cooled for about 5 minutes, plus a little extra, softened, for greasing the pan
1 teaspoon (5 ml) pure vanilla extract
For the raspberry filling
1 cup (12 oz jar) (340 g) seedless or seeded raspberry jam, thick and spreadable
2 teaspoons (6 g) cornstarch
1 tablespoon (15 ml) fresh lemon juice
1 teaspoon (2 g) lemon zest, finely grated
1 cup (125 g) fresh raspberries, rinsed, patted completely dry (whole berries) (optional)

Equipment (9)

9×9-inch (23×23 cm) metal or light-colored baking pan
Parchment paper
Large mixing bowl
Medium bowl
Small saucepan or microwave-safe bowl (for melting the butter)
Rubber spatula
Flat-bottomed measuring cup or glass (for pressing the crust)
Wire rack
Sharp chef's knife

Steps

Before you start

Plan for about 3 hours 15 minutes in total. The bars must cool for 2 hours before cutting, or the jam will run and the bars will crumble.
Melt the butter and let it cool for about 5 minutes. It should be warm, not hot.
Use a thick, spreadable jam. Runny jam can seep into the crust and make it soggy.
Use old-fashioned rolled oats, not instant or steel-cut.

1
Preheat and line panOven 350°F / 175°C
- Position a rack in the center of the oven and heat to 350°F (175°C).
- Lightly grease the bottom and sides of a 9×9-inch (23 cm) pan with a little softened butter.
- Line with a strip of parchment that covers the bottom and hangs over two opposite sides as a sling.
- Press it flat against the butter.
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Ready when: Parchment lies flat with no gaps in the corners.
Tip: The overhanging sling is what lets you lift the whole slab out for clean cuts.
2
Mix dry ingredients
- In a large bowl, whisk together the flour, oats, brown sugar, baking soda, salt, and cinnamon.
- Rub any brown sugar lumps between your fingers until the mixture looks evenly sandy.
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Ready when: No visible lumps of sugar or pockets of baking soda.
3
Add butter and vanilla
- Pour the cooled melted butter and the vanilla over the dry ingredients.
- Stir with a spatula, then finish with your hands, squeezing the mixture until it forms moist, shaggy clumps with no dry flour at the bottom of the bowl.
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Ready when: A handful squeezed in your fist holds together and breaks into big clumps.
Tip: If the butter is hot it will melt the sugar and make the crumble greasy, so let it cool first.
4
Press the crust
- Set aside 1 cup (about 150 g) of the crumble mixture in a medium bowl for the topping.
- Tip the rest into the prepared pan and press it into a firm, even layer, using the bottom of a flat measuring cup to compact it, especially in the corners.
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Ready when: The surface is level and firmly packed, with no loose crumbs.
Tip: Press firmly. A loosely packed crust makes bars that fall apart when cut.
5
Bake the crustOven 350°F / 175°C
- Bake the crust at 350°F (175°C) for 15 minutes, until the edges look lightly golden and the surface looks dry and set.
- While it bakes, make the filling.
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Ready when: Edges are light golden and the center looks dry and set when touched lightly.
6
Make the filling
- In a medium bowl, stir the cornstarch into the lemon juice until smooth.
- Add the jam and lemon zest and stir until fully combined and loosened slightly.
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Ready when: No white streaks of cornstarch remain.
Tip: The cornstarch thickens the jam as it bakes so the filling doesn't run when you cut the bars.
7
Fill the bars
- Remove the crust from the oven (leave the oven on).
- Spoon the jam mixture over the warm crust and spread it gently to within ¼ inch (6 mm) of the edges.
- If using fresh raspberries, scatter them evenly over the jam.
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Ready when: The jam forms an even layer with the crust visible only as a thin border.
Tip: Leaving a small border keeps jam from caramelizing and sticking to the pan sides.
8
Add the topping
- Crumble the reserved topping mixture evenly over the filling, breaking it into pea-sized to marble-sized clumps.
- Pat very lightly so the clumps sit on the jam but do not flatten.
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Ready when: Jam is mostly covered, with a few small jammy gaps showing.
9
Bake the barsOven 350°F / 175°C
- Bake at 350°F (175°C) for 28 to 32 minutes, rotating the pan halfway through, until the topping is deep golden brown and the jam is bubbling around the edges.
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Ready when: Topping is deep golden brown and jam visibly bubbles at the edges of the pan.
Tip: Pale topping means underbaked bars that stay soft. Wait for real golden color.
10
Cool completely
- Set the pan on a wire rack and let the bars cool at room temperature for 2 hours, until the pan is no longer warm to the touch.
- For the cleanest slices, chill for 30 extra minutes (included in the cooling time shown).
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Ready when: Pan bottom feels cool and the jam no longer jiggles when the pan is nudged.
Tip: Cutting warm bars makes the jam ooze and the crumble fall apart.
11
Lift and slice
- Run a thin knife around the edges of the pan, then use the parchment sling to lift the slab onto a cutting board.
- Cut into 4 rows by 4 rows to make 16 squares, wiping the knife clean between cuts.
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Ready when: Squares hold their shape with clean sides.
Tip: Use a gentle sawing motion rather than pressing straight down so the topping doesn't crack.

Good to know

Tips

Press the crust firmly with a flat-bottomed measuring cup. This is the main step that keeps the bars from falling apart.
Bake in a metal or light-colored pan. Dark pans can over-brown the edges before the center is set.
If your jam is loose, simmer it in a saucepan for 3 to 5 minutes and cool it before using.
Dry the fresh raspberries thoroughly so excess moisture does not make the filling watery.

Make ahead

"Bake the bars up to 2 days ahead and store, uncut, covered at room temperature, then slice before serving. The crumble mixture can also be made and refrigerated, covered, up to 24 hours before baking. Let it sit at room temperature for 15 minutes before pressing into the pan."

Storage & reheating

Room temperature: airtight container, up to 3 days. Refrigerator: up to 7 days; bring to room temperature for 20 minutes before serving, or warm a bar at 300°F (150°C) for 5 minutes. Freezer: wrap individual bars well and freeze up to 3 months; thaw overnight in the refrigerator or for 1 hour at room temperature.

Substitutions

seedless or seeded raspberry jam → Strawberry, blackberry, apricot, or cherry jam or preserves. Use the same weight and choose a thick jam. Taste first and omit the lemon zest if the jam is already tart.
light brown sugar → Dark brown sugar. Gives a deeper molasses flavor and slightly chewier crust.
all-purpose flour → 1:1 gluten-free baking flour blend. Use certified gluten-free oats too. The bars will be slightly more delicate, so cool them fully and chill before cutting.
unsalted butter → Vegan butter sticks. Use a stick-style vegan butter, not a spread from a tub, and melt as directed.