[header] How to clean dark cooking oil [title] Skim the oil. [step] When you fry foods, the foods leave pieces behind that cloud up the oil. Skimming the oil takes away some of these pieces, though you'll need to take further steps to remove all of them. 
Skimming the oil just takes care of the big pieces. [substeps] Use a skimmer to get rid of any floating pieces of food that are on top of or inside the blackened oil in the pot.