I have always found the sweet potato casseroles North Americans serve at Thanksgiving and Christmas dinners cloyingly sweet. They were often made from canned sweet potatoes and had too much brown sugar and/or maple syrup. And whoever thought it was a good idea to top that off with miniature marshmallows was misguided.
Sweet potatoes can be delicious. Those with dark flesh seem to be more moist and tasty than the pale fleshed ones. The best way to eat them is roasted; some Hong Kong street vendors still sell these. At home, it's probably easier to bake them. Scrub the skins and dry them. Pierce the tubers with a fork to prevent them from bursting, rub the skins lightly with vegetable oil and bake in a 180-degree Celsius oven until tender. Serve with butter, salt and pepper.
The flavour of fresh sage and thyme goes beautifully with this root vegetable. Sweet potato ravioli with beurre noisette and sage is easy to make if you use thin wonton wrappers (wonton pei). Bake the tubers until tender, as above. When cool enough to handle, cut them in half lengthwise and scoop the flesh from the skins. Mash the flesh and add a little soft brown sugar - just enough to enhance the flavour. Sprinkle with salt, black pepper and a little grated nutmeg. Lay the wonton wrappers on a flat surface and put a teaspoonful of the mixture in the centre of each. Lightly brush the edges of the wrappers with beaten egg and cover with another wrapper, pressing firmly so the edges adhere.
Chill for at least an hour. Bring a large pot of water to the boil, lower the heat and carefully add the ravioli. Simmer gently so the ravioli don't fall apart. When the ravioli float to the surface, lift them out with a slotted spoon. Heat unsalted butter in a pan until it sizzles, then lower the heat and cook, swirling the pan occasionally, until the butter turns a medium-light brown and gives off a nutty aroma. Add julienned fresh sage leaves and sizzle over medium heat until they become fragrant. Pour the butter over the ravioli, sprinkle with sea salt, freshly ground black pepper and toasted pinenuts and serve immediately.
Sweet potato mash is an excellent accompaniment to roasted or grilled meats. Peel the tubers and slice into rounds of the same thickness (so they cook evenly). Boil until just tender - do not overcook or they'll become waterlogged. Drain thoroughly and mash, adding unsalted butter and heavy cream until it reaches the right consistency. Sprinkle in a little soft brown sugar. Add finely chopped fresh sage or thyme, salt and freshly ground black pepper.
