I just boil my chicken breasts for shredded chicken, as it only takes a short time. However, if you want to use the crock pot, thaw them first! I would also do more than 2, especially since the crock pot should be at least half full. A little salt & pepper, maybe some onion and celery for flavor. About 3 hours on high 5-6 on low. I cook and shred mine, then add a can of broth (or use your own)to moisten, then add bread crumbs as a binder. I would cook more than the two and then re-freeze if you can't use the rest of it fast enough, then you would have most of a meal already cooked, just heat and eat.

Tami

chicken breasts will turn to cardboard in a crock pot....poach them in a little flavored broth.
Put a couple of cups of water in a sauce pan, add some chunks of onion and a clove of garlic, a stalk or so of celery...hand full of parsley...or some dried...maybe a bay leaf....table spoon or2 of lemon juice....simmer for 10 minutes....put in the chicken breasts....still frozen or thawed....doesn't matter add water to cover the chicken....and simmer until when you cut into them they are no longer pink. The amount of time depends on the number of chicken breasts....likely 30 to 45 minutes.....when no longer pink, turn off and allow to cool in the broth for about 30 minutes....remove and shred...or chop or refrigerate for later.

But for the shredding you can be done with the whole thing in an hour.

I'm not a big fan of poached chicken but I would defrost them overnight - or in the microwave, which I usually do- then quickly saute them in a hot pan. Ready to shred in ten minutes or less of cooking time. However, I prefer for shredded meats, a combination of outside crunchy and inside tender. If you season the breasts well before a quick, hot, saute, then you will have both. And, imho, browned meat (the browned part of the chicken) adds a huge flavor impact.

Thanks everyone. This is what I have done so far. I boiled 4 breasts, good idea Tami, cooled and shredded. I saved the broth, thanks Lindac, and after straining added to the shredded meat and saved in refrigerator. Now tomorrow I think I will add a little garlic, onion, salt, pepper and what else??? Put in crock pot, turn on low as we leave the house for church and maybe it will be ready for some good sandwiches when we get home, about two hours. How am I doing? What other spices have me puzzled but I hope I will think of them. Crushed red pepper, parsley, bay leave?? Don't have any celery.

No crock pot......it's the long cooking of a very lean meat that turns it to cardboard.....chewey strings.
Put the broth and onions, garlic, some jalapenos, a bit of cilantro...if you like cilantro....and perhaps a cut up tomato or 2...or half a can of whole plum tomatoes.
cook that while you are at church....then turn it to high and add the shredded chicken until just hot.

OK Sounds good. Thanks Lindac. Good idea on the jalapenos.