Lemon Crumb Bars: A Perfect Balance of Sweet and Tart

These Lemon Crumb Bars combine a buttery shortbread base with a creamy lemon filling, all topped with a golden crumb topping. The recipe creates three distinct layers that work together perfectly: a firm, cookie-like crust, a smooth, tangy lemon center, and a crispy, sweet crumble top.

The Perfect Lemon Bar Science

The success of these bars lies in the interaction between the sweetened condensed milk and fresh lemon juice. The acidity of the lemons causes the proteins in the condensed milk and egg yolks to thicken naturally, creating a silky-smooth filling that sets beautifully when baked.

Ingredients

For the Buttery Crumb Base and Topping:

• 2 1/3 cups (290g) all-purpose flour
• 1/2 cup (100g) granulated sugar
• 1/2 cup (100g) light brown sugar, packed
• 3/4 teaspoon salt
• 1/4 teaspoon baking powder
• 12 tablespoons (170g) unsalted butter, melted and cooled

For the Lemon Filling:

• 1 (14 oz/396g) can sweetened condensed milk
• 4 large egg yolks, room temperature
• 2 tablespoons (30ml) heavy cream
• 1/8 teaspoon salt
• 2/3 cup (160ml) fresh lemon juice (from 4-5 lemons)

Step-by-Step Instructions

1. Preparation

1. Preheat oven to 350°F (175°C)
2. Line a 9×9 inch baking pan with parchment paper, leaving overhang
3. Gather all ingredients at room temperature

2. Making the Crumb Mixture

1. Whisk together in a large bowl:

• All-purpose flour
• Both sugars
• Salt
• Baking powder

1. Pour in melted butter
2. Mix until crumbly but cohesive
3. Reserve 1/3 of mixture for topping

3. Preparing the Base

1. Press remaining crumb mixture firmly into pan
2. Ensure even distribution
3. Bake for 15 minutes until lightly golden

4. Creating the Filling

1. While base bakes, whisk together:

• Sweetened condensed milk
• Room temperature egg yolks
• Heavy cream
• Salt

1. Gradually add lemon juice while whisking
2. Continue mixing until smooth and slightly thickened

5. Final Assembly and Baking

1. Pour filling over hot crust
2. Sprinkle reserved crumbs evenly over top
3. Bake 15-20 minutes until:

• Top is golden brown
• Center is set but slightly jiggly
• Edges are lightly browned

6. Cooling and Setting

1. Cool completely at room temperature
2. Refrigerate minimum 4 hours
3. Cut into squares using a sharp knife

Pro Tips for Success

• Always use fresh lemon juice, not bottled
• Ensure egg yolks are at room temperature
• Press the base firmly for a solid foundation
• Let bars cool completely before cutting
• Use a hot knife for clean cuts
• Store in refrigerator for best texture

Storage Guidelines

• Refrigerator: Up to 5 days in airtight container
• Freezer: Up to 3 months, wrapped individually
• Serve cold or slightly chilled for best flavor

Nutrition Information (per bar, makes 16)

• Calories: 285
• Fat: 12g
• Carbohydrates: 42g
• Protein: 4g
• Fiber: 0.5g
• Sugar: 30g

These Lemon Crumb Bars are perfect for any occasion, from casual gatherings to elegant dessert tables. Their make-ahead nature and ability to be served chilled make them ideal for entertaining. The combination of buttery crumb and tangy lemon creates an irresistible dessert that’s sure to become a favorite.