Seasoning You can season your steamer just like a cast iron skillet. Wipe the entire steamer, inside and out, with food-grade vegetable oil that has a high smoking point (soybean, canola). Place it in a 400 degree oven for 30-60 minutes. Allow to cool completely. Repeat as needed.
Storage Wash with warm soapy water and a soft-bristled brush. Rinse well and dry thoroughly before storage. Keep in a cool, dry place with the lid off. Place 2-3 paper towels inside to help absorb any moisture/humidity that may accumulate.
Rust Removal Rust will naturally occur. Remove it from your cast iron steamer with a piece of fine-grade sandpaper. Rinse the steamer, dry thoroughly with a soft towel, then re-season.