Achiote Oil is an oil that has been coloured with annatto seed (also known as achiote seed.) The annatto seed itself adds no flavour, just colouring.
Flavour may sometimes by added as well, though, with a dried chile pepper or a bay leaf.
Some Vietnamese batters are made with annatto oil to make the batter a richer colour when cooked. The Vietnamese may also rub chicken or duck skin with the oil before cooking.
In Latin American and Mexican cooking, it is used for frying fish or poultry, and adding colour to stews, rice dishes, tamales or casseroles.
To make the oil, simmer 1/2 cup annatto seed in 1 cup (8 oz / 250ml) of flavourless vegetable oil for about 10 minutes or until the oil has a rich golden colour. Strain out and discard the seeds, and refrigerate the oil.
Store in refrigerator in tightly sealed container for up to 1 year.