With Hot Foot Powder, the aim is for the person to step in it, therefore you need to reapply it. If this is a stubborn situation, you may need to reapply it regularly and possibly follow it up with some move-away spellwork. I like bottle spells where you dispose of them in running water.
With herbal magic, and especially hoodoo - which Hot Food Powder is a part of the hoodoo cannon - it is not all intent. That is New Age, Neo-Pagan dogma. When working with botanical helpers such as Red and Black Pepper, both ingredients in most Hot Foot recipes, we are relying on the inherent powers of the botanicals to assist us in our task. Therefore, you need them to get into the target.
Since this is a hot foot situation where you want this person to hot foot it out of your house, then they need to step in it. Best of luck.