How to Season and Maintain a Cast Iron Burger Smasher

Seasoning is polymerized oil, a paper-thin layer of hardened fat that bonds to cast iron at high heat. This layer prevents moisture from reaching the bare metal, which is what causes rust. It also creates a smooth surface that releases food naturally, improving non-stick properties over time. A well-seasoned cast iron burger press feels slick to the touch and shows a dark, almost glossy finish.

New cast iron comes with a factory seasoning that works, but it is thin. The first few months of regular cooking thicken and strengthen it. Each time you oil and heat the press, you add another microscopic layer. This is why cast iron becomes more useful the longer you own it. Some presses arrive in bare metal and require seasoning from scratch; most kitchen tools, including the top smash burger smasher models on the market, start with at least a light factory coat that you simply maintain.

Seasoning happens in the oven at high heat, which is where oil hardens into that protective layer. The process is straightforward and takes about an hour from start to finish, though most of that is passive baking time. Start with a clean, dry press, then apply a very thin coat of oil, wipe away the excess, and bake. Repeat for multiple layers to build a stronger finish. Below are the exact steps to follow.

Not all oils season cast iron equally. The oil must have a high smoke point, meaning it does not break down and burn at the temperatures required for seasoning. Grapeseed oil, avocado oil, and refined vegetable oil all work well. Canola and peanut oil are acceptable but less ideal. Avoid butter, coconut oil, and extra-virgin olive oil, which smoke at lower temperatures and create a sticky, flaky finish instead of a smooth layer.

Many casters swear by the oils they started with, but the chemistry is consistent: high smoke point equals successful seasoning. A thin coat is always better than a thick one, no matter which oil you choose. The excess oil that stays on the surface does not polymerize into the smooth layer you want; it just gets sticky and eventually turns rancid.

Between deep seasoning sessions, maintain the press with a simple post-cook routine. After washing and drying, apply the thinnest possible coat of oil with a cloth, then wipe it away almost entirely. That minimal oil prevents surface oxidation without building up sticky residue. Store the press in a dry place, and over time that layer thickens naturally from cooking and micro-maintenance.

Once every few months, run the press through a full seasoning cycle in the oven, especially if you notice any dull patches or light discoloration. This keeps the surface strong and prevents rust from gaining a foothold. How to season and maintain a cast iron burger smasher really comes down to consistency; five minutes of care every few weeks beats panic-mode stripping and reseasoning after rust appears.

Never soak a cast iron burger press in water or put it in the dishwasher. Even brief soaking invites rust, especially on a pre-seasoned press where the outer layer has not yet bonded fully to the base metal. Avoid acidic foods, wine-based sauces, or tomato-heavy marinades on cast iron; acid strips seasoning. Store the press somewhere dry; a damp basement or humid garage accelerates rust formation.

Do not use steel wool or harsh scrubbing pads, which scratch away seasoning. A soft cloth or plastic scraper is enough for cleanup. If rust spots appear, address them immediately with fine-grit sandpaper or a specialized rust eraser, then re-season the affected area. Catching rust early is far easier than watching it spread.