Foaming Frenzy Pumpkin This trick will send your jack-o-lantern into a foaming frenzy. Carve the jack-o-lantern like normal. Then take a small bowl and place it in the cavity of the pumpkin on the bottom. Dissolve a packet of yeast in warm water. (This is normally 3 TB warm water to 1 TB or dry yeast.) Pour 1/2 cup of hydrogen peroxide 20% strength into the bowl inside the pumpkin. (This is stronger hydrogen peroxide than you normally would have at home. You will find this at a beauty supply store. You can use varying strengths. We used 20% and 30%.) Add some food coloring and a good squirt of dishwashing liquid to the hydrogen peroxide. Then when the yeast is all dissolved and activated, pour it into the hydrogen peroxide liquid and put the lid on the pumpkin.