Cinnamon Apple Bars

Preheat your oven to its highest temperature setting, which should be marked as 350 degrees F (or 175 degrees C). Next, take a 9-inch square baking pan and apply a thin layer of cooking oil to prevent sticking.

In a separate bowl, combine 1 cup of all-purpose flour, 2 teaspoons of baking powder, 1/4 teaspoon of ground cinnamon, and a pinch of salt. Using a sifting motion with your hands or a fine-mesh sieve, incorporate 2 tablespoons of granulated sugar and the remaining 1 teaspoon of cinnamon into this mixture.

Meanwhile, in a separate small bowl, whisk together 2 tablespoons of granulated sugar and the remaining 1 teaspoon of cinnamon until well combined.

In a large mixing bowl, combine 1/2 cup of brown sugar, 1/2 cup of granulated sugar, and 4 tablespoons of melted butter. Using a wooden spoon or spatula, mix these ingredients until they form a smooth consistency.

Next, crack in 1 egg and whisk in 1 teaspoon of vanilla extract. Gradually incorporate the flour mixture into this wet ingredient mixture until just combined, taking care not to overmix.

Add 1 diced apple and 1/2 cup of chopped walnuts to the mixture, stirring until they are evenly distributed.

Spread this mixture evenly into your prepared baking pan and sprinkle the cinnamon-sugar topping over the top of the mixture.

Bake in your preheated oven for 25 to 30 minutes, or until the top of the mixture springs back when pressed lightly with your finger. Remove from the oven and let cool completely in the pan before cutting into 16 equal-sized squares.