Using a double boiler or a pot of boiling water with a smaller pot or stainless steel bowl fitted inside, melt cocoa butter, shea butter, coconut oil and liquid oil together over medium heat.
When the oils are completely liquid, remove them from heat and place the bowl/pot in the freezer to firm up. Make sure to use a stainless steel vessel that can handle the transition from hot to cold.
When the mixture is hardened enough that you can press your finger in it and make an imprint, remove it from freezer.
Add essential oils (if using) and vitamin E (if using) to the bowl.
Using a stand mixer or hand mixer, start whipping the mixture on the slowest setting and gradually increase the speed as the mixture softens. Whip until it transitions from yellow to white, then lower the mixer speed back down and whip a little more to make it extra fluffy.
Once the body butter is light and fluffy, add the arrowroot powder and whip again to mix it in.
Store in an airtight glass jar and keep out of direct sunlight, which promotes oxidation and may cause the homemade body butter to melt if it heats up too much.