Heat olive oil in a pot over medium heat and sauté the onion, carrot, and celery for 5 minutes until softened.
Add the minced garlic, dried thyme, and dried rosemary, cooking for another minute until the aromatics are fragrant.
Pour in the chicken broth and add the whole chicken breast, bringing the liquid to a gentle simmer.
In a separate small bowl, whisk together the whole wheat flour, baking powder, sea salt, and black pepper.
Stir the Greek yogurt into the flour mixture until a soft, slightly sticky dough forms.
Drop small spoonfuls of the dough into the simmering broth and immediately cover the pot with a tight-fitting lid.
Steam for 12 minutes without lifting the lid to ensure the dumplings become light and fluffy.
Remove the chicken breast, shred it with two forks, and return it to the pot before serving hot.