There's more than one way to core an apple without an apple corer, but one of the easiest methods requires you to cut off all four sides of the apple, as close to the core as possible without cutting into it. The apple should be placed upright on a clean cutting board to cut off the sides. It takes a bit of guesswork to determine where the core is, but you should get a better sense of this with practice. When done properly, you are left with a rectangular core, which you can discard.
- Prepare the apple
Wash the apple under cool water. If you need the apple peeled, use a small paring knife and work your way around the apple from the top to the bottom in a spiral. You can also use a vegetable peeler.
- Get a cutting board
Place the apple upright on a clean cutting board. Position a sharp chef's knife near the top of one side of the apple. The knife should be somewhat close to the stem, but not too close, so you don't cut into the core.
- Slice off the apple sides
Slice down the side of the apple, cutting it off completely. Rotate the apple and cut off the remaining three sides in the same manner. Discard the rectangular core, and slice or chop up the apple sections as needed.