Are you sure it's tin and not stainless steel? Cookware, as in pots and pans? Below is a stainless steel pan. Does it look like this?
What is the best way to clean tin cookware?
Since you did not mention the type of cookware, here is a
link where you will find several ways to clean kitchen utensils made from
different materials: https://www.realsimple.com/food-recipes/tools-products/cookware-bakeware/how-clean-cookware. I find hot water and dishwashing
gel very useful. I barely utilise the dishwasher, what do you think about it? I
hope that my answer is helpful to you. J
Don't cook in it.