Set the pot on the stove on medium low heat. Dice the pancetta and ham and add them to the pot. It's going to take 10-15 minutes for those to get nice and crispy. Stir the pork occasionally keeping an eye on it to make sure it isn't burning.
While the pork is crisping we can prepare our aromatics and get our soffrito variation assembled. Dice the onion, celery, and tomato. Mince the garlic, and place the prepared soffrito ingredients into a bowl.
After the meat is crisp (10-15 minutes) add in the soffrito (onion, celery, tomato, garlic) and cook on medium low heat stirring occasionally until the liquid is gone, approximately 10 minutes. While the soffrito is cooking down prepare your greens.
Wash and slice the greens into 1/2 inch wide pieces. Personal preference if you leave the stems or not, some of my greens had little nettles on them so I ended up cutting them off, but for greens like kale, collards, and char I like to use most of the stems.
When the liquid is gone from the pot, add in the stock and scrape all that deliciousness from the bottom of the pot. Add in the paprika, red pepper flakes, lemon zest, and mix in the greens.
Turn the heat up to high, bring the mixture to a simmer, then turn the heat down as low as possible and cooke for two hours with a lid partially ajar. Check on the collards every once in a while and give them a stir.
After 2 hours your greens should be good to go! Add in 1 tbsp. of butter to finish off the dish. Taste at this point and season with salt and pepper to your taste. We got a lot of salt out of the meat and the greens so be careful! If you like your collards less liquidy just take the lid off and reduce the dish for a couple of minutes at a simmer.