Beans are a nutritional powerhouse, they're filling, and they're cheap. But they're also bland. To get the most out of your beans, you need to give them flavor, which requires adding herbs and spices. There's a certain amount of personal preference involved when it comes to determining the "best" spices in anything, and there are many possibilities to try.
Spices can be expensive, and you may not be able to afford a great deal of them. You'll get more bang for your buck if you can get the most variety out of the smallest number of spices. For instance, salt and pepper alone may add all the flavor you want.
Besides salt and pepper, probably the most versatile spice to add to beans isn't a spice at all. It's vinegar. No matter what kind of bean dish you're making, vinegar can probably make it better. Vinegars are cheap, so you can experiment here. Try rice vinegar or apple cider vinegar. A couple of tablespoons of vinegar to a fresh pot of beans right at the beginning of cooking may smell characteristically sour at first, but after a couple of hours it will add a complex dimension of flavor that is very subtle and hard to identify: the perfect "secret ingredient."
Granulated garlic is another spice known for its versatility and cost-effectiveness. Much cheaper than fresh garlic, but almost as potent, granulated garlic adds savory-bitter notes to your final product.
Lemongrass, dried and finely shredded, goes well with beans in a variety of dishes. It adds a subtle sour undertone, not unlike lemon, as the name suggestions, but not nearly as tart or simplistic on the palette as lemon. Add a tablespoon or two of lemongrass to any bean dish at the start of cooking.
In clear or cream dishes, try a sparing amount of poultry seasoning. Beans are similar enough in texture to meat that you can get some meat-like results. In bean dishes with tomatoes, try a generous amount of Italian seasoning, along with lemon zest.
Cumin and coriander evoke the Near East and India, and can be used in bean dishes handed down from that part of the world. Try also adding a couple of cloves. And red pepper, cayenne or Tabasco will give your beans spicy heat.
As a matter of American tradition, beans and barbecue are joined at the hip. When making barbecued beans, start with a base of one part ground mustard, five parts Worcestershire sauce, five parts red pepper, 10 parts granulated garlic and 20 parts brown sugar. After it's cooked and ready to serve, add a different kind of "spice" in the form of whiskey.
Bean soup is a classic. If you're having beans with vegetables and meat, add rosemary, sage, marjoram, oregano, basil and bay leaves. Let the beans be washed over with the flavor of the herbs and broth, and add salt to taste.