In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and pepper.
In a small bowl, stir together the buttermilk, butter and chives. Slowly pour the buttermilk mixture into the dry ingredients, stirring just until the dough comes together. Be careful not to overmix it, or the dumplings will be tough.
Drop tablespoon-sized (15 gram) dollops of dumpling dough on top of the stew, leaving a little room between each one.
Cover and simmer for 10 to 12 minutes. The dumplings should have grown in size by roughly fivefold, and the interior should look like a soft dinner roll. If they are not fully cooked, cover and cook for 2 minutes more.
If you like browned dumplings like we do, preheat your broiler while the dumplings are poaching. Once the dumplings are puffed, place the pot in the oven, uncovered, and broil until their tops are golden brown, 2 to 5 minutes, depending on your broiler.
Divide the chicken stew and dumplings among bowls, and top with more chives, if desired.