Heat olive oil in a dutch oven or large stockpot over medium heat.
Add the chicken thighs, and sprinkle with salt and pepper.
Sear the chicken for 2-3 minutes, then flip and sear the other side. Remove the chicken from the pot and set aside (they don't need to be cooked fully since they will poach in the soup)
Add the diced carrots, celery and onion to the pot. Cook until tender, about 5 minutes. Add in the garlic and cook for an additional 30 second.
Sprinkle the flour into the pot, stir until the veggies are coated.
Pour in the chicken broth. Add the salt and poultry seasoning. Stir to combine.
Add the chicken back in and bring soup to a boil, reduce heat and let the soup simmer for about 20 minutes. Chicken should reach a temperature of 165℉.
Shred the chicken.
In a small bowl add the cornstarch. Carefully remove about 1/2 cup of broth from the pot, whisk this into the cornstarch until combined. Pour this into the pot and whisk into the stew.
In a medium size bowl combine the dry ingredients for the dumplings (flour, salt and baking powder) stir with a fork to combine.
Pour in the melted butter, and milk. Stir to combine.
Add in the herbs and garlic. Mix.
Spoon the dough into the soup, keep the size consistent to help with even cooking.
Cover and let simmer for 15-20 minutes until the dumplings are cooked through.
Serve warm and enjoy.