Description
These Lemon Crumb Squares feature a buttery oat crust topped with a luscious lemon custard filling and crumbly topping. Perfectly balanced with bright citrus flavor and sweet richness, they make a delightful dessert or snack for any occasion.
Ingredients
Scale
Crust and Topping
- 1 cup all-purpose flour
- 1 cup old-fashioned oats
- ¼ teaspoon salt
- ¾ teaspoon baking soda
- 10 tablespoons unsalted butter, melted
- ½ cup packed light brown sugar
- 1 teaspoon pure vanilla extract
Filling
- 1 (14 oz) can sweetened condensed milk
- 2 tablespoons sour cream or plain yogurt
- 1 large egg yolk
- ¼ cup freshly squeezed lemon juice
- 1 heaping tablespoon finely grated lemon zest
- 1 teaspoon pure vanilla extract (additional, for filling)
Instructions
- Preheat Oven and Prepare Pan: Preheat your oven to 350°F and line an 8×8-inch baking pan with parchment paper to prevent sticking and allow easy removal of the bars.
- Mix Dry Ingredients: In a medium bowl, combine the all-purpose flour, old-fashioned oats, salt, and baking soda, ensuring even distribution of the leavening.
- Combine Wet and Dry for Crust: In another bowl, whisk together the melted unsalted butter, packed light brown sugar, and 1 teaspoon vanilla extract. Add the dry ingredients to this mixture and stir until just combined to form the dough.
- Reserve Dough for Topping: Set aside ¾ cup of the dough for the crumbly topping. Press the remaining dough evenly into the bottom of the prepared baking pan to form the crust layer.
- Bake the Crust: Bake the crust for about 10 minutes or until it’s lightly golden. This helps to firm up the base before adding the filling.
- Prepare Lemon Filling: In a bowl, whisk together the sweetened condensed milk, sour cream or plain yogurt, large egg yolk, freshly squeezed lemon juice, finely grated lemon zest, and additional 1 teaspoon vanilla extract until the mixture is smooth and well combined.
- Assemble the Bars: Pour the lemon filling over the warm baked crust. Crumble the reserved dough evenly over the filling to create the crumb topping.
- Final Bake: Return the pan to the oven and bake for 17 to 20 minutes until the top is golden brown and the filling is set in the middle.
- Cooling and Serving: Allow the lemon crumb squares to cool completely in the pan to firm up, then slice into approximately 16 squares and serve.
Notes
- Use fresh lemon juice and zest for the best bright citrus flavor.
- Make sure to cool the bars completely before slicing to ensure clean cuts.
- You can substitute sour cream with plain Greek yogurt for a tangier taste.
- Store leftovers in an airtight container in the refrigerator for up to 4 days.
