Adobo seasoning, sazon, and sofrito are items you should be able to find in your local food store. If not, try any Spanish store.
Boil 2 cups of water or enough to cover chicken breast. Add 1 large spoon of sofrito, 1 tbs of adobo, 1 pack of sazon and 3-4 chicken breasts and about 1/2 a lime or lime juice. Boil for about 45 minute or until chicken will be easy to shred.
Drain chicken breast and let it cool. Then start shredding chicken (I use my hands or 2 forks).
Put the shredded chicken back into the pot at medium heat and add about 1/2 cup of water, 1/2 can of tomato sauce, 1 teaspoon of adobo, 1/2 lime and stir. Keep adding a little adobo and lime to your liking of the taste. Let simmer for about 20 minutes or until most of the juice has evaporated.
Use your favorite kind of corn tortillas (I like the white corn tortillas, they are easier to fry).
In a medium frying pan add 1/2 cup of oil (vegetable or corn oil).
Put 1 tortilla in a at a time, let it get hard on one side, then flip to other side and right before it gets hard, fold in half and remove from oil and let it drain.
Add your cheese, lettuce, tomato and other good stuff you like on your tacos. Enjoy!