Preheat the oven or air fryer to 325℉.
Season the chicken thighs all over with salt and black pepper.
Add chicken thighs, skin side down, to a large pot. Set the heat to medium. Let the chicken thighs sear undisturbed, until golden brown around the edges, about 10-12 minutes. Flip and cook the second side for about 2 minutes more. The chicken will not be fully cooked at this point.
Remove the chicken to a plate and carefully peel off the skin and place on a lined sheet tray.
Transfer the chicken skins to the oven (or to an air fryer) and cook until very crispy, about 20-25 minutes. Set aside to cool.
Meanwhile, add the onion to the pot with the chicken fat. Cook for about 3-4 minutes, until translucent.
Add in the garlic, carrot, celery and fennel. Season with salt and pepper and cook until the veggies are soft, 5-8 minutes.
Move veggies off to the side of the pot to make space to make a quick roux. Add the butter to the pot and melt. Stir in flour, stirring consistently, then stir the roux into all the veggies. Cook for 1 minute.
Add the corn, then the chicken back in.
Add in the stock, the bay leaf and thyme (tied together with butcher’s twine if you have it).
Simmer the soup over medium low heat, stirring occasionally, until the chicken is fully cooked.
If the soup seems like it is getting too thick as it is cooking, cover it with a lid. Add in more chicken stock or water as needed.
Remove the bay leaf and thyme and discard. Remove chicken from the soup and shred with two forks. Discard the bones.
Add the shredded chicken back into the soup along with the peas and cream. Taste and adjust seasonings. Add in lemon juice.
Serve soup topped with dill, black pepper, grated parmesan cheese, lemon zest, croissants and crushed pieces of crispy chicken skin.