Preheat oven to 350°F (175°C).

Grease a 13 x 9 x 2-inch pan.

In a large bowl, blend sugar, eggs, and oil with a fork.

Add flour, cinnamon, baking powder, and salt to the mixture.

Mix with a large spoon until combined.

Peel, core, and cut apples into thick slices (approximately 1/8 inch thick).

Fold the apple slices into the batter.

Pour the thick batter into the greased pan.

Bake for 1 hour, or until a toothpick inserted into the center comes out clean.

Let cool slightly before slicing and serving.