Ah...Chicken Paprikash...comfort food that has enough "exotic" to make it a treat but is easy enough for everyday. This is basically Southern Fried Chicken Swimmin' in Gravy, Hungarian Style.
I take about a cup of flour and put it in a bowl or on a plate and mix in about a tablespoon of seasoned salt for the dredging. Dredge each of the pieces of chicken, knocking off excess flour.
Heat the fat in a cast iron skillet over medium heat. If you are using butter, wait until the bubbling stops. Otherwise, when the fat shimmers, it is ready. Put each of the pieces of chicken skin side down in the pan, without crowding the pan too much. One chicken can be done in a 10 inch or larger fry pan. If you have more chicken or a smaller pan, do this in batches. You want to brown the chicken, not poach it. Leave the chicken alone for 5 minutes (it should be brown, even dark brown, but not burned) then use tongs to flip it over on the other side for 5 minutes. Pull the chicken out and set aside.
Pour off excess fat, keeping about a tablespoon in the pan.
Add the onions and cook in the remaining fat until somewhat clear...again, browning is OK, but no burning. Add the chicken stock and the paprika and stir to get the gnarly bits off the bottom of the pan. Add the chicken back into the pan and bring the liquid to a simmer. Cover, and lower the heat, allowing the chicken to simmer for 30-45 minutes.
Remove the chicken to a platter or large bowl. I like to taste the gravy at this point for salt and pepper. Then whisk in the sour cream, and continue to heat (still on low) until it bubbles lightly. (Really, you don't even have to reheat, but it gives all the bits and pieces to come together in a luscious sauce. But no high heat, no boiling...you'll just curdle it all).
Pour the gravy over the chicken. Serve with noodles, dumplings or mashed potatoes.