Slice onion, and peel and cut carrots into large chunks; place into crockpot.
Season pork chops with 1/2 teaspoon salt and 1/4 teaspoon pepper (if you are not using a low-sodium broth, omit the salt); place on top of veggies and pour broth over the top. Cook on low for 6-8 hours.
Approximately 30 minutes before serving, cook quinoa as directed on package.
Roughly chop spinach and dice apples; add to cooked quinoa.
In a small bowl, whisk together olive oil, juice of the lemon, 1 teaspoon lemon zest, salt, and pepper. Pour over quinoa and mix to coat evenly.
Serve pork chops with onions, carrots, and quinoa salad on the side.