The art of boiling yams is a rather simple one, but mastery requires careful attention to yam size and preparation, water temperature and overall boiling time. Ideally, a boiled yam is soft and pliable but is neither so firm that it is hard to work with nor so fragile that it disintegrates easily. To get this result, cooks must pay careful attention to each step of the process. Tips for boiling yams include peeling the produce, cutting it into manageable chunks and adding it to water only after the water has begun to boil. From there, the tubers must be monitored to ensure proper cooking time.
There are many approaches to boiling yams, and it is difficult to pin down a single “right” way. In large part, this is because what is right or wrong is largely dictated by recipe and by the cook’s intentions for the finished product. Still, there are a few tips that are fairly ubiquitous. These tips usually apply to sweet potatoes and yams indiscriminately; there is a biological difference between the two, but the terms are commonly used interchangeably.
First, the yams should be cut into small segments. Boiling will cook yams by exposing their surface to water so hot that it cooks them all the way through. It is possible to boil a yam by dropping it whole into a pot of water, but this often takes several hours and can lead to uneven results. Cooks can improve the process by boiling yams that have been cut into at least quarters. The smaller the pieces, the faster they will cook.
Peeling the yams in advance is another common tip. Although the peels pack in a lot of nutrients, they usually are rough and do not always soften much when boiled. They can add an unwanted taste and texture to the finished dish. Yams usually are easiest to peel when whole, which makes peeling them before chopping an attractive option for many.
Cooks who want to retain some of the peels' nutrients often peel most — but not all — of the yams before boiling them. One in three might be left with the peel on, for instance, or a single yam might be peeled in stripes. Boiling yams with the skin on usually requires cooks to thoroughly scrub the vegetables before boiling them. The water temperature will kill most bacteria, but it will not eliminate the dirt and debris that so often clings to yam skin.
As far as the actual cooking process goes, it usually is best for the cook to wait for the water to reach a rolling boil before adding the yam sections to the pot. There should always be enough water to completely submerge the pieces. Cooking with yams is easiest when all of the produce's surfaces are receiving the same treatment.
Water is not the only boiling option, though. Liquids such as stocks or broths will impart a unique flavor. Most water substitutions occur in recipes where the boiling liquid will be retained as either as a soup or a sauce base. In most cases, the yams flavor the broth as much as the broth flavors the yams.
The liquid might take a few minutes to return to a boil after the yams have been added. After it does, however, the heat should be turned down to a simmer, and the boiling yams carefully monitored. Precise timing depends on several factors, including the size of the yam sections and total water volume. In most cases, though, boiling yams takes 20-30 minutes.
Cooks should regularly check on the progress of the boiling yams by poking the sections with a fork. When the pieces feel tender to the touch and are easy to prick, they are nearing completion. Finished yams retain their shape but mash easily. They should be drained into a colander, then either returned to the pot for mashing or emptied out for further use in other recipes. There are many ways of preparing yams after they are tender.