Creating these delicious Peach Crumble Bars is easy when you follow these steps:

1. Preheat your oven: Set your oven to 350°F (175°C) and grease a 9×9-inch baking pan.
2. Prepare the crust: In a mixing bowl, combine the flour, sugar, baking powder, and salt. Stir in the melted butter and vanilla extract until the mixture is crumbly.
3. Press into the pan: Take about two-thirds of the crust mixture and press it firmly into the bottom of the prepared baking pan to form the base.
4. Prepare the peach filling: In another bowl, mix the sliced peaches with lemon juice and cinnamon (if using). Spread this mixture evenly over the crust in the baking pan.
5. Add the crumble topping: Sprinkle the remaining crust mixture over the peach filling, ensuring it covers the fruit evenly.
6. Bake: Place the pan in the preheated oven and bake for 30-35 minutes, or until the topping is golden brown.
7. Cool: Remove from the oven and let cool in the pan for 10-15 minutes before transferring to a wire rack to cool completely.
8. Cut into bars: Once cooled, slice into squares or rectangles for serving.

By following these simple steps, you’ll have a batch of delectable Peach Crumble Bars that are sure to impress!