Some cake recipes I've seen require buttermilk, but it's an ingredient I have been unable to find in Hong Kong. Can I use regular milk or cream instead?
Buttermilk is a fermented, sour milk product with a higher acid content than regular milk and a slightly thicker consistency. For baking soda to produce carbon dioxide, which makes the cake rise, the acid comes from the buttermilk.
You can find powdered buttermilk in boxes (I've seen it in Oliver's in the Prince's Building, tel: 2810 7710); just mix with water. Its advantage over fresh buttermilk is that it has a longer shelf life. You can also make your own soured milk by mixing one tablespoon of freshly squeezed, strained lemon juice with a cup of whole milk and letting it stand until it looks slightly curdled.
Can you recommend a good, all-purpose knife?
No, because such a thing doesn't exist. Some knives are good for most purposes, but none can be used for everything. Unless you are extremely skilled and dextrous it's going to be difficult for you to use a heavy chef's knife with a 25-centimetre blade to remove the tough membrane from a leg of lamb. But if your knife is too small you'll struggle when using it to chop things as heavy and dense as potatoes or carrots, or when attempting to cut a watermelon in half.
If you are an ordinary, all-round cook, you can probably get by at first with two knives. A chef's knife with a 20-25cm blade or a thin-bladed Chinese cleaver will serve for cutting and chopping vegetables, slicing meats, jointing chickens or even slicing a cake. A sharp paring knife with a straight 10cm blade is necessary for more precise and delicate work such as boning chicken parts or trimming vegetables. As you cook more, you'll probably want to add to your set of knifes: one with a long, serrated blade for slicing home-made bread or splitting a cake into layers, a narrow knife with a semi-flexible blade for filleting fish, or a heavy Chinese cleaver for chopping through poultry bones.
