You do need a candy thermometer to make your own marshmallows. There is no way of getting around this. If you don't own a thermometer, buy one. They are cheap. I promise that after one batch you will be putting that thermometer to good use. You also really do need a stand mixer but these can possibly be made with a hand held. Just be prepared to stand there for a while. I haven't tried to make them this way, however, so can't guarantee they will work. You can cut these anyway you like. I have made them into cubes using a pizza cutter and also used cookie cutters to cut shapes, as in the pictures above. The marshmallows will keep for at least a week in an airtight container.