The best cakes come from the best ingredients, and you'll want to choose the best chocolate you can find. This may not, however, be the most expensive brand. There is a simple way to know whether you are selecting a quality chocolate: Check the ingredients label. If it lists any fat other than cocoa butter, it's not the good stuff. (Many manufacturers add palm kernel oil, coconut oil or other vegetable fats to their chocolate because they are cheaper than cocoa butter.)
Here's some more thoughts on what to look for in chocolate:
Milk Chocolate: If you love the smooth, creamy flavor of milk chocolate, you are not alone. Although I am a big fan of milk chocolate bars, I usually don't espouse milk chocolate in baking, and instead choose darker chocolate for a more assertive flavor.
Semisweet Baking Chocolate: Almost all of the recipes in my book contain some amount of semisweet baking chocolate. If you prefer darker, more assertively flavored chocolate, you may substitute exactly the same amount of bittersweet chocolate in any of my recipes. Do check the ingredients label on the packaging, which should read (in this order): chocolate (unsweetened), sugar, cocoa butter, soy lecithin (an emulsifier), vanilla extract. As mentioned above, do not purchase chocolate that contains any fat other than cocoa butter.
Unsweetened Baking Chocolate: Look at the packaging of unsweetened chocolate. It should list one ingredient -- chocolate. Unsweetened chocolate is not palatable on its own, but it is the heart and soul of all chocolate confections. It is the juice, if you will, of the cacao plant. Unsweetened chocolate is present in some form in all other chocolate. Unsweetened chocolate is by composition more than 50 percent cocoa butter, the remaining amount being what is termed cocoa solids.
Unsweetened Cocoa Powder: Cocoa is produced by pressing almost all of the cocoa butter out of unsweetened chocolate. The flavor intensity of cocoa is diminished by exposure to air, so I recommend purchasing small containers and keeping them tightly sealed. Look at the container closely before purchasing to make certain you are not selecting a breakfast cocoa drink mix.
White Chocolate: It can't be chocolate -- it's the wrong color! But since sweetened chocolate contains more than 50 percent cocoa butter, then white chocolate, which is primarily composed of cocoa butter, must indeed be chocolate. The ingredients listed on a package of white chocolate should be sugar, cocoa butter, milk, soy lecithin (an emulsifier) and vanilla extract. Remember, palm kernel oil (or any other vegetable fat, for that matter) need not apply.