cut the soap bars into small squares
melt the soap in a bain-marie, or a bowl set over a pot of boiling water
fill the mold half way with soap. Set it in the freezer for 10 minutes
place your prize on top of the hardened soap and pour in the remainder of the melted soap
back in the freezer for another 15 minutes and it’s done!
pop them out and watch your kids clean their nails as they try to dig out the prize