If you want to make crushed pineapple out of pineapple chunks, the first thing you need to do is cut the pineapple into small pieces. You can either use a knife or a food processor to do this. Then, put the pineapple chunks into a plastic bag and use a rolling pin to crush them. Once the pineapple chunks are crushed, you can add them to a recipe or enjoy them as a snack.