Add lemon juice, olive oil, salad dressing mix, garlic, and capers to a small mixing bowl, and whisk everything together.
Place chicken in crockpot and add lemon juice mixture to the top.
Next, add chopped onions and bell peppers to the crockpot.
Set crockpot on high for 4 hours. (Remember, every crockpot is a little different, so you may need to adjust the time accordingly!)
Once it's done, shred the chicken and let it sit in its juices. (Trust me, it's delicious!)
Notes
I love this chicken served over white rice or cous cous. Don't forget to add the juices from the crockpot and throw some feta cheese on top! It is divine!