Place the chicken thighs in a dish and add the eggs. Toss well to make sure the chicken is well coated in egg.
In a separate dish combine the breadcrumbs, garlic powder, black pepper, cayenne and a good pinch of salt.
One at a time, coat the chicken thighs in the breadcrumbs and set aside while you get the oil ready.
Heat about 1/2” of oil over medium-high heat in a 12” cast iron skillet. When it’s hot (drop in a couple of breadcrumbs and if they sizzle, it’s ready).
Add in the chicken thighs (in batches, if necessary so as to not crowd the pan) and cook for 2-3 minutes per side until well browned.
Remove the chicken to a plate and discard the excess oil.
Mix the oregano into the marinara sauce and add to the skillet.
Add the chicken to the skillet, on top of the sauce.
Evenly scatter the cheese over the chicken.
Top the cheese with the pepperoni slices.
Bake at 375 for 20 minutes until the cheese is well browned an bubbly.