One of the first things to learn about when you're ready to take the next step and get serious about improving your bbq results, is how various spice flavors interact with one another. Some meats taste better with more salt than others--pork for example. Some meats taste better with a little more heat in the rub than others--brisket or even chicken other examples. However, in the final analysis, what's good to you might not be good to someone else. If cooking for others, it's best to stick to middle-of-the-road flavors rather than veering too far in any one direction.
There are plenty of commercial bbq rubs on the market. It's fun to experiment with them and try out different flavors and styles of rubs. Some are hot, some are sweet, some are salty and some have a near perfect blend of heat, sweat and salt; but, the best way to learn what tastes good to you is by learning to make your own bbq rub.
Making your own rub will teach you more about flavors and "blends" of flavors than buying someone else's idea of what they think tastes good. You may end up going back to the commercial rub eventually, but by experimenting with your own rub too, you'll learn what to look for in a commercial rub.
Let's begin be defining a bbq rub....
BBQ Rub = Mixture of spices that are combined are sprinkled or "rubbed" onto the meat before cooking. This could be a mixture as simple as equal parts of salt and pepper, or it could be something as complicated as a mixture of 10 -12 difference spices with subtle differences.
Here's a good basic rub that you can use to get started. After using it a few times you may find that you'd prefer a little more pepper, a little more sugar, or something else added, but this will give you a good base to start out.
Basic BBQ Rub Recipe
3 tablespoons of sea salt
3 tablespoons of granulated sugar
3 tablespoons of mild paprika
1 teaspoon of granulated garlic
1 teaspoon of granulated onion
1 teaspoon of black pepper
1 teaspoon of white pepper
Basic BBQ Rub # 2
1/2 cup paprika
1/4 cup ground black pepper
1/3 cup salt
1/3 cup sugar
2 tablespoons chili powder
2 tablespoons garlic powder
2 tablespoons onion powder
1 teaspoon cayenne
Some other optional items you may to experiment with by adding to or subtracting from this recipe from time to time include: nutmeg, oregano, cummin, cayenne pepper, chipotle powder.
I've found that cummin goes well with pork and oregano goes well with beef.
Apply this rub to the meat you're preparing to bbq and let it marinade in the refrigerator for 8 hours or more (overnight works well) prior to cooking. This will allow the rub to penetrate the meat better than if you apply it directly before placing in the smoker.
In my opinion, it's better if the rub is a little on the hot side when you mix it up because after cooking, rubs tend to lose a little of their heat, especially if you use foil during the cooking process.