To prepare Heavenly Summer Peach Bars, follow these simple steps for a successful and enjoyable baking experience:

1. Preheat Oven: Start by preheating your oven to 350°F (175°C). Grease an 8×8-inch baking pan or line it with parchment paper.
2. Mix Dry Ingredients: In a large bowl, combine the flour, sugar, baking powder, and salt. Stir until blended.
3. Incorporate Wet Ingredients: Add the melted butter, eggs, and vanilla extract to the dry mixture. Stir until the mixture is smooth.
4. Pour Base into Pan: Transfer the batter to the prepared baking pan, using a spatula to spread it evenly across the bottom.
5. Prepare the Filling: In another bowl, mix the diced peaches, cinnamon, lemon juice, cornstarch, and half of the remaining sugar. Gently fold until the peaches are well coated.
6. Add Filling to Bars: Spoon the peach mixture evenly over the batter, spreading it gently to make sure it’s distributed well.
7. Bake: Place the pan in the preheated oven and bake for 35-40 minutes. The bars should be golden on top, and a toothpick inserted in the center should come out clean.
8. Cool: Once baked, remove the bars from the oven and let them cool in the pan for about 15-20 minutes.
9. Slice: After cooling, cut the bars into squares or rectangles as preferred.

These simple steps guide you in creating Heavenly Summer Peach Bars that are sure to impress anyone who tastes them!