These Lemon Oatmeal Crumble Bars are a delightful balance of zesty citrus and buttery oats. With a soft, creamy lemon filling layered between a golden oat crumble crust and topping, they’re the kind of treat I love to make when I want something simple yet impressive. Naturally sweetened and easy to prepare, these bars work beautifully as a snack or a light dessert, especially alongside a cup of tea or coffee.
Ingredients
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
For the crust and topping:
1 1/2 cups old-fashioned rolled oats
1/2 cup coconut sugar (or light brown sugar)
1 1/4 cups all-purpose flour
1/2 teaspoon baking soda
1/2 teaspoon salt
3/4 cup unsalted butter, melted
1 teaspoon pure vanilla extract
For the lemon filling:
1 (14 oz) can sweetened condensed milk
1/4 cup lemon juice (freshly squeezed)
1 tablespoon lemon zest
2 large egg yolks
Directions
I preheat the oven to 350°F (175°C) and line an 8-inch square baking dish with parchment paper, leaving some overhang on the sides for easy lifting.
In a medium bowl, I combine the oats, flour, coconut sugar, baking soda, and salt.
I stir in the melted butter and vanilla extract until the mixture turns into a crumbly dough.
I press about two-thirds of the oat mixture evenly into the bottom of the prepared pan to form a solid crust.
In a separate bowl, I whisk together the sweetened condensed milk, lemon juice, lemon zest, and egg yolks until smooth and creamy.
I pour the lemon filling over the crust and use a spatula to spread it evenly.
Then I sprinkle the remaining oat crumble mixture over the lemon layer.
I bake the bars for 25–30 minutes, until the top is golden and the center looks set.
After removing the pan from the oven, I let the bars cool completely at room temperature, then refrigerate them for at least 2 hours before slicing.
Servings and timing
This recipe yields 9 bars.
Prep Time: 15 minutes
Cook Time: 30 minutes
Chill Time: 2 hours
Total Time: 2 hours 45 minutes
Calories per bar: approximately 285 kcal
Variations
I sometimes swap the lemon juice for lime juice for a tropical twist.
For extra texture, I like to add shredded coconut or chopped nuts into the crumble topping.
To make them gluten-free, I use a 1:1 gluten-free flour blend instead of all-purpose flour.
If I want a slightly less sweet version, I reduce the sweetened condensed milk by a few tablespoons and add a bit of Greek yogurt for creaminess.
Storage/Reheating
Once cooled and sliced, I store these bars in an airtight container in the refrigerator for up to 5 days. They also freeze beautifully—just wrap each bar in parchment paper and freeze in a container or zip-top bag for up to 3 months. I let them thaw in the fridge or at room temperature. These bars don’t need reheating, but I enjoy them slightly chilled or at room temp.
FAQs
How do I know when the lemon bars are done baking?
I look for a golden top and a set center. The filling should no longer jiggle when gently shaken.
Can I use bottled lemon juice instead of fresh?
I’ve tried it, but the flavor is never as vibrant. Freshly squeezed lemon juice makes a noticeable difference in taste.
Do I need to refrigerate the bars before serving?
Yes, chilling helps them firm up and makes them easier to slice cleanly. I always refrigerate for at least 2 hours.
Can I double the recipe?
Absolutely. I double the ingredients and bake them in a 9×13-inch pan. The baking time may need a few extra minutes.
What’s the best way to slice these bars cleanly?
I use a sharp knife and wipe it clean between each cut. Chilling the bars first also helps them hold their shape.
Conclusion
These Lemon Oatmeal Crumble Bars have quickly become one of my go-to desserts. They’re easy to make, satisfyingly zesty, and have just the right amount of sweetness. Whether I’m baking for friends or just want a little something sweet on hand, this recipe always delivers. Give them a try and I think you’ll find them just as irresistible.
Recipe:
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Lemon Oatmeal Crumble Bars
- Total Time: 2 hours 45 minutes
- Yield: 9 bars
- Diet: Vegetarian
Description
These Lemon Oatmeal Crumble Bars feature a creamy lemon filling layered between a buttery oat crust and crumble topping. Sweet, tart, and simple to prepare, they make a refreshing treat for any time of day.
Ingredients
1 1/2 cups old-fashioned rolled oats
1 1/4 cups all-purpose flour
1/2 cup coconut sugar (or light brown sugar)
1/2 teaspoon baking soda
1/2 teaspoon salt
3/4 cup unsalted butter, melted
1 teaspoon pure vanilla extract
1 (14 oz) can sweetened condensed milk
1/4 cup lemon juice (freshly squeezed)
1 tablespoon lemon zest
2 large egg yolks
Instructions
- Preheat the oven to 350°F (175°C) and line an 8-inch square baking dish with parchment paper, leaving some overhang for easy lifting.
- In a medium bowl, combine the oats, flour, coconut sugar, baking soda, and salt.
- Stir in the melted butter and vanilla extract until the mixture becomes crumbly.
- Press about two-thirds of the mixture evenly into the bottom of the prepared pan to form the crust.
- In a separate bowl, whisk together the sweetened condensed milk, lemon juice, lemon zest, and egg yolks until smooth.
- Pour the lemon filling over the crust and spread evenly with a spatula.
- Sprinkle the remaining oat crumble mixture over the lemon layer.
- Bake for 25–30 minutes, until the top is golden and the center is set.
- Allow the bars to cool completely at room temperature, then refrigerate for at least 2 hours before slicing.
Notes
Swap lemon juice for lime juice for a tropical variation.
Add shredded coconut or chopped nuts to the crumble topping for extra texture.
Use a 1:1 gluten-free flour blend to make the bars gluten-free.
Reduce the sweetness by using less sweetened condensed milk and add Greek yogurt for creaminess.
Store bars in an airtight container in the fridge for up to 5 days or freeze for up to 3 months.
No reheating needed; enjoy chilled or at room temperature.
- Prep Time: 15 minutes
- Cook Time: 30 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 bar
- Calories: 285
- Sugar: 18g
- Sodium: 120mg
- Fat: 15g
- Saturated Fat: 9g
- Unsaturated Fat: 5g
- Trans Fat: 0g
- Carbohydrates: 34g
- Fiber: 2g
- Protein: 4g
- Cholesterol: 55mg
