How to Season a Cast Iron Skillet with Bacon Grease

Seasoning your cast iron doesn’t have to be intimidating. Applying thin layers of fat or oil and baking at a high temperature is all it takes. Whether you are seasoning a new unseasoned cast iron pan or restoring an old neglected pan, the seasoning process will be similar.

 In this post we will take a closer look at the benefits of cast iron. What it means for a pan to be seasoned, different oils and fats to use along with their properties. We will complete the seasoning process with bacon grease, including how to collect your bacon fat and the right way to store it. We will end with tips on the best way to care for your cast iron skillet.

Do I need to season my cast iron?

A new pan will usually come seasoned, if yours didn’t, the seasoning process is the same. An unseasoned pan will appear gray in color rather than a hard rich black.  Even if your new cast iron skillet came pre-seasoned, you may want to complete the home oven seasoning. The seasoning from the manufacturer is usually weak and more susceptible to being stripped from mild soaps.

An old pan may need to be re-seasoned after neglect and improper washing. A well seasoned pan should have a hard dark black appearance. If food is sticking, the pan looks gray, there is pitting, rust or visible damage, it’s time to re-season. Read to the end of this post for tips on caring for your cast iron in the future.

What does it mean to have a seasoned cast iron pan?

“Seasoned” is a common term used to describe a pan that has gone through the process of polymerization. When thin layers of oils and fats have been applied and exposed to high heat, it becomes bonded to the iron as carbonized oil. This carbonized oil is what prevents food from sticking to the cast-iron. When a pan has been properly seasoned it will keep your pan in good condition for many years to come, and be a joy to cook with.

Issues to look for in a cast iron skillet

New cast-iron pans are expensive. Restoring an old pan is a great way to save money and save another item from ending up in the landfill. While cast-iron pans are known for being tough, here are a few things to watch out for when looking through your local thrift store. 

Major pitting

Most pitting should be minor, and will be filled in with a few layers of seasoning. If there is major pitting in a central cooking area, this may cause frustration when cooking. Pitting is mainly caused by rust.

Warped pan

Warping is usually caused by large temperature fluctuations. Such as placing that hot skillet into cold water to cool it down. Once a pan is warped there is no way to fix it. If the warp is fairly minor you may still be able to use it. However larger warps can cause food to cook unevenly, and should be avoided.

Cracks

A crack in the pan means it’s time to retire it. Even with a minor crack, once a pan is exposed to heat it can break. Cracks tend to hide under rust and imperfections but once noticed you should discontinue use immediately. 

Major rust

Rust may look scary but oftentimes with cast-iron you can get rid of it. When it comes to a major rust problem though, you will need to decide how much effort you are willing to put in and assess the damage already done.  Continue reading on how to fix even a moderately rusted pan.

Saving bacon grease for use

Step 1. Cook your bacon to your preferred method. We usually bake it in the oven on a baking sheet lined with tin foil. Bake at 375 degrees F for 20 minutes, flipping halfway. You could also pan fry which is an easy way if cooking just a few strips of bacon.

Step 2. Once your bacon is cooked, remove the bacon from the baking sheet or pan. Allow the grease to cool enough to handle.

Step 3. While the bacon grease is cooling, prepare your glass jar. Placing a coffee filter, cheese cloth or using a fine mesh strainer over your jar. This will remove any bits of bacon from the grease. Skipping this step will cause your bacon fat to go rancid quicker. While the grease is still warm, before it solidifies, carefully pour through the filter and into your jar. 

Step 4. Store bacon grease in a sealed container in the fridge.  If left at room temperature bacon grease has a shelf life of only 2 hours, according to food safety experts. Before using your grease, check that the color is still white and has not gone yellow. Also smell to ensure it does not smell rancid or sour.

A major benefit of using leftover bacon grease is reusing something that may otherwise go to waste. Bacon grease has a moderate smoke point of 325 degrees F. 

Oils and fats for seasoning a cast iron

Here is a short list of other possible oils to use. While this list is not exhaustive, it does include the most recommended. You will want to find an neutral cooking oil with a high smoke point.

Avocado oil

Refined Avocado oil is a favorite for many. It has a high smoke of around 500 degrees F and is neutral in flavor.

Vegetable oils, Canola oil, melted solid shortening

These are the oils most of the Cast-iron manufacturers recommend. They vary in a smoke point of 400-490 degrees F. They are all neutral in flavor, readily available and economical. 

Grapeseed oil 

Grape seeds oil is another oil many of the cast-iron manufacturers recommend. It has a smoke point of 420 degrees F and is neutral in flavor. In more recent years the effects of heating grapeseed oils have come into question, so many home cooks may wish to avoid it. 

Flaxseed oil

Flaxseed oil has been touted by many to be the oil to use, stating that because it is a drying oil it hardens well. However flaxseed has a low smoke point of only 225 degrees F. It is also fairly expensive and can be hard to procure. 

Preparing your pan for seasoning

If you are working with an old pan you will need to prepare it before you season it. Using a steel wool or stiff brush give the pan a good scrub. Exposing your pan to soap right now is alright, as you will be seasoning it shortly. This should remove any surface rust. If your pan has extra rust that did not come off, continue on to the vinegar soak. 

Vinegar soak

Find a container that will allow you to fully submerge your pan. Fill with a solution of half distilled vinegar and half water. Place your pan in the vinegar solution and ensure it is fully submerged. Checking on your pan every 30 minutes to see if the rust has released. Remove the pan from the solution and scrub with a stiff brush, return to the solution if necessary. Repeat as needed, checking every 30 minutes. Leaving longer than necessary can cause damage to the cast-iron. Once you are satisfied, remove the skillet from the solution and rinse thoroughly. 

Give your pan a wash with dish soap and hot water.  Dry well right away to prevent rust damage. Using a cloth alone may leave the pan damp. Place your pan on the stove over medium heat for 1-2 minutes to allow it to fully dry. Be aware that when your pan is stripped of all seasoning it is extremely susceptible to rust, coat with oil and prepare to season immediately.

How to season a cast iron skillet

Now that your pan is washed, prepared and you have your fat of choice you are ready to complete the seasoning process. 

Step 1.  Heat your oven to 400 degrees F if using bacon grease. If you are using vegetable oil, canola oil or shortening, heat to 450 degrees F and avocado oil heat your oil to 500 degrees F. Place one rack in the center of the oven and a second below that. Place a sheet of tin foil on the lower rack to catch any potential drips.

Step 2. Using a rag or lint-free paper towel place a small amount of fat, up to a tablespoon in the pan. Coat your skillet with the oil. Be sure to cover the entire skillet in the oil, both inside of the pan, outside and the handle.  With a clean cloth thoroughly wipe away excess grease, the pan shouldn’t appear greasy at all. It is important to use thin layers of oil. Thick layers of fat will not carbonize fully and evenly, leaving bumps or sticky spots.

Step 3. Place your skillet facing down directly above the baking sheet on the upper rack. Bake for 1 hour. Once the hour is up, turn off the oven and allow to cool for 2 hours with the door closed.  Your pan will still be hot.

Step 4. Repeat steps 2 and 3 as needed. For a new unseasoned cast iron pan you may need to repeat 4-6 times. For a skillet needing to be re-seasoned, or a new pre-seasoned skillet,  1-3 should be enough.

Caring for your well seasoned cast iron pan

Now that you have taken the time to season your pan, here are the best practices to protect it. With regular use and a small change in habits your pan should stay well seasoned for a long time to come.

Let your skillet cool slightly before washing, but remove any stuck on food while it is fresh. 

Avoid placing a hot skillet in cold water, this can cause warping. 

Avoid harsh detergents, and soaps. Although mild soaps we use today should not cause too much damage. 

Do not soak your pan in water. 

Fully dry your pan after cleaning by placing on a burner set to medium for 1-2 minutes.

Taking the time to properly care for your pan will give you great reward when cooking with it. A well-cured pan that was received proper care will last for generations.

Tell me in the comments below where your favorite thing to make in your cast iron.

Recipes you can make in your cast iron

Sourdough discard crepes