I have a Helia smoker in my kitchen that is suitable to do basic smoking but not professional by any means. Many know that smoking is a way to preserve and can be used to preserve meats and fish. The smoke dehydrates the foods while the smoke’s acids and other compounds protect the food.
But a smoker is a good tool to add flavor, and I cooked white small beans on the stove and added flavor compounds I needed, garlic fresh, onion caramelized, carrots, mint, parsley, and after cooking dried herbs, Zatar, sumac and paprika. Later I will take the mixture and run it in the thermomix and make a Tuscan bean soup, and add some bread croutons, olive oil and a dash of fresh parsley.
So back to smoking, there are two ways, cold and hot. The Helia is special in that it has two separate controls, one for the smokers temperature and the heating element for the tray that holds the wood dust. I rarely use the smoker above the minimum temperature which is 10+°C. The cold smoke leaves a film over the foods as the smoke deposits a condensated stream of smoke flavor.
Hot smoking is more difficult and requires more experience and finesse. If you decide to cook and smoke fennel, the temperatures should be 90°C or in that range otherwise the vegetable is uncooked. You can have a smoked fennel which is nice but cooked vegetables with smoke is another thing.