The gizzard and heart can yield some of the toughest bites you'll find in a chicken; both organs get a lot of work throughout the life of the bird and won't gracefully reach tenderness when fried without a little coaxing. Relieve them of their marked chewiness with the Southern treatment: a little pounding from the meat mallet and a cultured buttermilk bath.
Tenderizing
Rinse the gizzards and hearts under cool water and drain them on paper towels. Pat the gizzards and hearts dry with a paper towel and transfer a handful of them to a cutting board.
Cover the gizzards and hearts with a couple of sheets of plastic wrap and tuck the edges under the cutting board. Cover the plastic wrap with a thin cloth or kitchen towel.
Strike the gizzards and hearts several times with a meat mallet, the bottom of a saucepan, a rolling pin or whatever you have handy. You don't have to pound them to a uniform thickness, just strike them firmly a few times.
Transfer the gizzards and hearts to a bowl with a few aromatics, such as sliced onions and garlic. Cover them in buttermilk, and let them marinate in the refrigerator for 24 hours.
Frying
Drain the gizzards and hearts in a colander. Slice them into 1/4- to 1/2-inch pieces. Heat 3 to 4 inches of peanut or canola oil in a tall, wide, heavy-bottomed pot -- Dutch ovens and cast-iron pans work best -- on the stove with medium heat.
Mix a few cups of flour with salt and spices -- paprika is a classic -- and pour it in a dish. Whisk a couple of eggs in a bowl until smooth.
Check the oil temperature with an instant-read thermometer and work the heat as needed to keep it between 350 and 375 degrees Fahrenheit.
Dip the gizzards and hearts in the egg one piece at a time, and then coat it heavily with the flour mixture. Use one hand for dipping and the other for flouring. Gently drop the pieces in the oil; move them around for a few seconds using a slotted spoon to keep them from sticking.
Cook the gizzards and hearts until golden brown, about 3 to 4 minutes. Then transfer the pieces to a plate lined with paper towels, again using a slotted spoon. Garnish with fresh herbs and serve straight away.
Tip
As an alternative to deep frying, saute the gizzards after slicing them. Heat a few tablespoons of oil over medium-high heat and saute the pieces until golden brown on both sides, about 6 minutes, turning frequently.
Warning
Gizzards and hearts should reach 165 degrees Fahrenheit during cooking. Use an instant-read thermometer to check one if you're unsure.
References
Writer Bio
A.J. Andrews' work has appeared in Food and Wine, Fricote and "BBC Good Food." He lives in Europe where he bakes with wild yeast, milks goats for cheese and prepares for the Court of Master Sommeliers level II exam. Andrews received formal training at Le Cordon Bleu.