We stew vegetables by letting them simmer in a bit of liquid and cooking fat. This is done in a covered pan, which can be placed in the oven, where the heat is more evenly distributed than in a casserole.
When briefly stewed, vegetables retain their appealing colour and flavour. We can apply this technique to all types of cabbage, for example, or to white radishes and carrots. We can also cook the vegetables for a longer period, resulting in a stew where the flavours blend. The main inconvenience of stewing is that vegetables lose their colour. This doesn’t necessarily mean their taste changes, however. Vegetables that tend to change colour quickly can actually be added later in the process, when two-thirds of the cooking time has elapsed; this will keep them crisp and they will retain the colour more easily.