Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking dish or line it with parchment paper for easy removal.
In a large mixing bowl, whisk together the flour, sugar, baking powder, baking soda, and salt until well combined.
Add the softened butter, eggs, and vanilla extract to the dry ingredients. Mix until the batter is smooth and well combined.
Fold in the diced apples, cinnamon, walnuts, and raisins (if using) until evenly distributed throughout the batter.
Pour the batter into the prepared baking dish, spreading it evenly.
Bake in the preheated oven for 30-35 minutes, or until a toothpick inserted in the center comes out clean.
Allow the Apple Delight to cool in the pan for about 10 minutes before slicing and serving.