In a large pot or Dutch oven, heat the olive oil over medium heat. Add the diced onion, sliced carrots, and celery. Cook for about 5 to 7 minutes, or until the onions are translucent and the vegetables have softened slightly. Stir in the thyme and garlic powder during the last minute of cooking.
Pour the chicken broth and the condensed cream of chicken soup into the pot. Whisk gently to combine the soup with the broth until the mixture is smooth. Bring the liquid to a gentle boil over medium-high heat.
Stir in the shredded cooked chicken. Taste the broth and add salt and black pepper as needed. Reduce the heat to a simmer to keep the liquid hot while you prepare the dumplings.
Open the tube of refrigerated biscuits. Cut each individual biscuit into four equal pieces (quarters). If the biscuits are very large, you can cut them into six pieces. This ensures they cook through evenly and stay light.
Drop the biscuit pieces one by one into the simmering soup. Do not stir too much; just gently push them down so they are covered by the liquid. Place a tight-fitting lid on the pot and simmer for 10 to 12 minutes. Avoid the temptation to lift the lid, as the steam is what cooks the dumplings perfectly.
Remove the lid and check a dumpling to ensure it is cooked through and no longer doughy in the center. The sauce should have thickened beautifully. Garnish with fresh parsley and serve immediately.