My mother-in-law demands I bring these 3 ingredient wonders to every family gathering. They always disappear before the main course is served.

These 3-Ingredient Lemon Bars are a brilliant shortcut to a classic bakery treat, using a lemon cake mix to create both a buttery shortbread-style crust and a golden, crumbly topping. By sandwiching a layer of vibrant lemon pie filling between the two, you get a dessert that is punchy, tart, and perfectly set without the need for tempering eggs or measuring out flour. The high butter content in the cake mix ensures the crust is rich and tender, while the “damp sand” texture of the topping creates those coveted crunchy peaks.

3-Ingredient Lemon Bars

Ingredients:

Step-by-Step Directions:

Step 1: The Buttery Base: Preheat your oven to 350°F. Lightly grease a 9×13-inch glass baking dish. In a medium bowl, combine the dry lemon cake mix with the melted butter. Stir with a fork until the mixture is evenly moistened and forms soft, crumbly clumps.

Step 2: The Firm Crust: Press about 2/3 of this buttery mixture into the bottom of your glass dish.

Tip: Use the flat bottom of a measuring cup to press the mixture firmly into the corners. A tightly packed base ensures the bars won’t crumble apart when you lift them out of the pan later.

Step 3: The Lemon Heart: Spoon the lemon pie filling over the crust and spread it into a smooth, bright yellow layer from edge to edge. Be gentle so you don’t disturb the crust underneath.

Step 4: The Crumble Top: Sprinkle the remaining 1/3 of the cake mixture over the filling. Let it fall in natural, uneven clumps rather than smoothing it out; these little “islands” of dough will turn beautifully golden and crisp in the oven.

Step 5: The Golden Bake: Bake for 25–30 minutes. You are looking for the lemon filling to bubble gently at the edges and the crumble topping to show light golden spots. The center should look set but still have a slight, soft give.

Step 6: The Essential Chill: Allow the bars to cool completely in the dish on a wire rack.

Tip: For those picture-perfect, clean-cut squares, refrigerate the cooled bars for 1–2 hours before slicing. This allows the fruit pectins in the pie filling to fully “lock” into a firm, sliceable texture.