This method works well on food stains, but is not especially effective on rust. This method eliminates the need for an overnight soak.

Simmer the mixture for a few minutes. Reduce the heat to a lower setting and allow the baking soda mixture to simmer in the cookware for several minutes. After it has simmered for a few minutes, turn off the heat. Baking soda is mildly abrasive, but only enough to help scrape away the stain. It is safe to use on your enamel cookware.

It is important to use a wooden spoon. Metal spoons can scratch the enamel surface and cause rust stains where the cast iron is exposed in the cracks. A wooden spoon with a flat edge will make scraping easier.

Continue squeezing lemon juice until you have covered all of the salt and made a paste over the stain. Scrub the area of the stain. Use a sponge or cloth to scrub the salt and lemon juice mixture into the the area of the stain. Watch to see if the stain appears to be coming out. [5] X Research source

Rinse the entire area with warm water and wipe it with a clean cloth. If you are cleaning a porcelain enamel covered cast iron bathtub, and cannot get the stains out, you can have the tub reglazed by a professional.

Look for cleansers which are labeled as being safe for use on enamel. Avoid scouring powders like Ajax and products with high acidic content like Vinegar. [9] X Research source Be sure that the cleanser you choose for a bathtub is 100% water soluble so it does not build up in the tub and cause a slippery surface. [10] X Research source

The product will dry during this process, but is still easily removed with a wet cloth. If you are leaving the product for more than one minute, test it on a small, inconspicuous area before using this technique on a large surface. Thoroughly rinse the cleanser from the surface once you have finished.

Coat your cookware with oil, cooking spray or butter before cooking to avoid sticking. Scrape residue from your cookware immediately after using it to keep the residue from caking on the enamel.

Gradual temperature change helps avoid warping.