To a large skillet, add in 2 tbsp of oil and heat over medium high heat. Add in all onions and allow to cook down for about 15 minutes, stirring frequently.
Lower heat to medium, add salt and allow onions to further cook down, stirring occasionally. This whole process should take about 45 minutes to an hour until the onions are fully caramelized. The onions will break down and be extremely softened and sweet.
In a separate bowl, season chicken thighs with all purpose seasoning, paprika, and black pepper.
Move the onions to the outer areas of the pans and add remaining oil to center of the pan.
Sear chicken thighs skin side down for about 8 minutes, and flip over once the skin is golden brown and crispy.
Add chicken broth and thyme to pan, and allow to cook for 20 minutes or until chicken is cooked through.
Start to place the onions on top of the chicken and add provolone slices to each piece of chicken. Lower heat once more to a low, cover, and allow cheese to melt.
Remove from heat and Serve immediately.