Every home cook has been there — reaching for the stick of butter after pulling out their trusty cast iron skillet. But is butter really the best choice for cooking in, or seasoning, cast iron?
The short answer is, as with any yes or no question, is it depends. You absolutely can cook with butter in cast iron, but there are some things to keep in mind. And when it comes to seasoning cast iron, butter’s a definite no-go.
Why We Cook With Butter
Butter adds a richness of aroma and depth of flavor distinct from all other fats because it’s made up of both milk fat and milk solids. Its “dairiness” makes otherwise ordinary meals like eggs, pancakes, or grilled cheese sandwiches delectable.
Cast iron, with its even heating, browns butter beautifully, bringing out its inner richness and making its flavor nutty and caramely thanks to what’s known as the Maillard reaction. But there’s a catch: butter burns easily — easier than oils — so it must be used with care.
Butter has a low smoke point at around 350°F. That means if you crank the heat up too high, your butter will start to smoke, burn, and turn acrid, ruining your food’s taste. The reason for this are the milk solids in the butter, which, like milk itself, scorch easily.
How to Cook With Butter
So, how can you make butter and cast iron work? Here are the keys:
Keep the Heat Low to Medium: This is non-negotiable. Don’t try to sear a steak in butter in your cast iron since searing requires high heat. Instead, use butter for gentle cooking — think frying eggs, sweating onions, or finishing a sauce.
Mix the Butter With Oil: If you need a little more heat, try adding a cooking oil with a higher smoke point along with the butter. (Equal parts oil and butter should work well for most recipes.) This will help raise the overall smoke point of the butter-and-oil mixture.
Add it Later: For dishes that require higher heat initially (like searing steak), start with a high-smoke-point oil, and then add a knob of butter towards the end of cooking for that final burst of flavor. Baste the food with the melted butter — it’s a chef’s secret for a reason!
The “High-Heat Butter” (and Other Alternatives): If you love the flavor of butter but want more heat tolerance, reach for clarified butter, also known as ghee. The clarification process removes the milk solids, leaving you with pure butterfat, which has a much higher smoke point (around 450°F). Ghee is fantastic in cast iron – you get that rich, nutty flavor without the burning.
Beyond ghee, here are some other excellent choices for high-heat cooking in cast iron:
Do Not Season Cast Iron With Butter
Now let’s talk about seasoning. Seasoning is the layer of polymerized (baked-on) oil that protects your cast iron from rust and that gives it a beautiful non-stick surface. Butter is not your friend here.
The milk solids in butter will burn and create a sticky, uneven seasoning. Plus, butter’s relatively low smoke point means it won’t properly polymerize (bond to the metal) at the high temperatures needed for seasoning. Almost immediately, the seasoning will start to flake off.
I season my cast iron cookware with grapeseed oil instead. Though you could technically use any cooking oil with a high enough smoke point, grapeseed oil remains stable at high heat, has a neutral flavor, and produces a highly dependable seasoning.
How I season my cast iron cookware:
- Clean and Dry: Make sure your pan is clean and completely dry.
- Thin Layer: Apply a very thin layer of your chosen oil all over the pan (inside and out). Wipe it off as if you’re trying to remove all of it – you want the thinnest possible coating.
- High Heat: Place the pan upside down in a preheated oven at 450-500°F for an hour.
- Cool Down: Let the pan cool completely in the oven.
- Optionally, repeat: One or two coats will give you good seasoning; repeating the process 3-6 times establishes and maintains the protective layer.
What We Just Covered
You can cook with butter in cast iron, do it carefully, and know its limits. It’s all about matching the fat to the task.
For everyday cooking, a little butter at low heat is fine. For searing and high-heat cooking, however, you should reach for ghee or a high-smoke-point oil.
And when it comes to seasoning, leave the butter in the fridge and grab the grapeseed oil. Your cast iron (and your taste buds) will thank you.