1-First Step: Preheat your oven to 350°F (175°C). Grease and line a baking pan with parchment paper to ensure easy removal of lemon bars.

2-Second Step: Combine the flour and softened butter in a mixing bowl and blend until crumbly to form the crust base.

3-Third Step: Press the crust mixture evenly into the prepared pan. Bake for 15-18 minutes or until lightly golden.

4-Fourth Step: While the crust bakes, whisk together eggs, sugar, lemon juice, lemon zest, and baking powder until smooth and frothy for the filling.

5-Fifth Step: Pour the lemon filling over the hot crust as soon as it comes out of the oven.

6-Sixth Step: Return the pan to the oven and bake an additional 20-25 minutes, or until the filling is set but still slightly jiggly.

7-Seventh Step: Let the bars cool completely on a wire rack, then refrigerate for at least 2 hours to fully set.

8-Eighth Step: Cut into squares and dust with powdered sugar before serving.

9-Adaptations: For vegan options, use plant-based butter and egg alternatives in the filling. For gluten-free, ensure the flour is gluten-free. Adjust baking times slightly if needed.