The key to adobo is the
vinegar and
soy sauce. Before
refrigerators were invented, cooking adobo was used as a way to keep meat for a few days in hot
tropical weather.
There are many many adobo recipes around. The amount and proportion of soy sauce and vinegar varies widely, and is dependent on the type and strength of both the soy sauce and vinegar.
If you are trying to cook adobo for the first time, try using equal amounts of soy sauce and vinegar, then adjust the proportion to suit your taste the next time you cook it. After about 3 tries, you should be able to find a mix that tastes good to you. I myself prefer about 1:2 proportion of soy sauce to vinegar.
Aside from the meat, vinegar, and soy sauce, all other ingredients are optional, though a lot of garlic is commonly added (you don't need to fry the garlic if you don't want to), as well as some crushed bay leaf and black pepper (whole peppercorns are traditional).
The simplest way to cook adobo is to throw in all the ingredients together in a pot, and let it simmer until the meat is cooked. This means you must have enough vinegar/soy sauce mixture in the pot such that it doesn't dry up before the meat is cooked.
As for the meat, chicken and pork are commonly used. Sometimes both together. You might also want to try using chicken feet. But beef adobo is just weird. Adobo is a very yummy dish, and is very easy to prepare. Enjoy