How do I season cast iron?  How do I know if my Dutch oven is fully seasoned?

What do I do prior to seasoning my cast iron?

For centuries now good Dutch ovens have been passed down from generation to generation.  If you do a good job seasoning and maintaining your cast iron Dutch oven, you too can keep it as a family heirloom.

These days some Dutch ovens come with the cast iron pre-seasoned.  In this case you might want to still check the seasoning and see if it has a nice black patina and there are no burrs or blemishes.  If it is to your liking you don’t have to re-season.  You can skip down to maintaining your Dutch oven.

If not pre-seasoned, the first thing you’ll notice is your new Dutch oven will be coated with a thick layer of wax.  This has been applied at the factory to ensure that you receive a rust free oven.  Before you season your oven, check for cracks or irregularities that might have occurred during casting.  Be sure to check the lid as well.  If you find any burrs they will need to be removed by filing or sanding.  The lid should also fit well to the kettle. 

Once you’ve inspected your oven, it is ready to remove the shipping or storage wax.  This can be done indoors or outdoors, but remember there will be a little smoke during the process of removing wax and seasoning the cast iron.  Because of the ability to reliably control the temperature, we prefer to perform these steps indoors with the windows open.

 Line a cookie sheet with foil and place it on the bottom rack of the oven.  Set your oven to 350º.  Place your cast iron in the oven face down on the top rack.  The hot wax drippings will land on the cookie sheet.  The same process should be done with the lid.  Again you’ll probably notice some smoke coming from the cast iron.  This is expected.  Once the smoking stops you’ll know that your cast iron is ready to be seasoned.  Remove the kettle and lid from the oven and allow cooling a bit before you wash it thoroughly with soap and water.  This will be the only time really that you should use soap.   Once the oven is fully dried and cooled a little it is ready to be seasoned.

How do I season cast iron?

Think of seasoning cast iron as a way to separate the metal from your food.  Without this protection your cast iron would retain some of what you cook leaving some meals a little distasteful.  Also, without the layer of oil your cast iron is likely to rust.  It is important then to make sure that you have a coating that covers the surfaces of your new oven.  There are differing opinions on what oils to use to season cast iron.  Some use vegetable shortening, vegetable oil, olive oil or commercially available cast iron conditioner.  We prefer olive oil over vegetable shortening or vegetable oil as extra virgin olive oil has a lower likelihood of going rancid. 

Here is how you season cast iron:

Again place a foil lined cookie sheet on the bottom rack.  The kettle and lid will be going on the top rack.

Preheat the oven to 425 degrees.

  1. Saturate a clean lint free rag with extra virgin olive oil and thoroughly coat all surfaces of the cast iron.
  2. Place in the oven face down.  As with removing the manufacturers shipping wax, the seasoning of the cast iron might produce a little smoke.
  3. Let the kettle and lid remain in the oven for one hour or until you notice that the smoking has stopped.
  4. Carefully remove from the heat and allow to cool enough to work with and add more oil with the lint free rag.
  5. Repeat to add three coatings of olive oil.

Once finished your cast iron should look a beautiful black color throughout.  Examine your cast iron for areas that don’t exhibit the black glasslike finish.  If there are gaps in the finish, add more oil.  You want the surface to be fully sealed.  As your Dutch oven gets used, it the seasoning will become more and more resilient. 

How do you know if your cast iron is fully seasoned?

The easiest way to tell that your oven is fully seasoned is the food will not stick to the inside surface.  There are only two ways for food to stick: you are cooking too hot or the cast iron isn’t fully seasoned.  Properly seasoned cast iron will have a completely non-stick surface.  It will look very shiny and even and it will be easy to clean.  If your food is sticking, give it another try with oil and a little over an hour in the oven at 425 and things should improve.  Seasoning takes time and a willingness to do it properly.  

Keep your newly seasoned cast iron clean and well maintained.