Thoroughly clean your skillet with soapy water and scrub off any bits and pieces stuck to the pan.
Pat the skillet dry, then place it on the stove for several seconds on medium heat to ensure no water remains.
Let the skillet cool to the touch, then dip a paper towel in peanut oil and coat the inside of the skillet.
Using a dry paper towel, wipe as much excess oil off as possible.
Set your burner to medium-high heat and heat the skillet for 7-10 minutes, while watching carefully.
It’s going to start to smoke, which reminds me, go ahead and turn on that vent fan and crack a window.
After about 7 minutes, you are going to notice the bottom of the pan slowly turning from a glossy finish to a dull greyish-black. That is the polymerization happening. The oil is being heated just past its smoke point, and it’s developing a solid, protective non-stick layer onto our cast iron skillet.
Once there is no glossy oil remaining, grab some oven mitts to turn off the stove, and remove the skillet from the heat to cool completely.
Notes
Allow your skillet to cool completely before checking and repeating the process if necessary.
Never oil the outside of a skillet when using the stovetop method. The burners should never come in contact with oil, or you risk a grease fire.
Always run proper ventilation and open a window if possible, as there will be plenty of smoke.
Wear oven mitts and make sure others in the house are aware of the hot skillets
Never leave your pan unattended while it's on the stove.