Dice the onion and celery, then slice the carrots, combine them in a mixing bowl and set them aside.
Add a quarter cup of butter to a large Dutch oven over medium heat and allow it to melt.
Once the butter has melted, add the prepared vegetables and cook them until the onions begin turning translucent and the celery starts to soften.
Season the vegetables with salt and pepper and give everything a good stir.
Stir in the minced garlic and continue cooking for another minute or two, just until it becomes fragrant.
Once the garlic is fragrant, add the remaining quarter cup of butter.
After the butter has melted, sprinkle in the flour and stir until it’s evenly incorporated throughout the vegetables.
Cook this mixture for about five minutes, stirring occasionally.
Slowly pour in the chicken stock while stirring and scraping the bottom of the Dutch oven.
Stir in the chicken bouillon powder and bring everything up to a gentle boil over medium heat.
Once the soup begins to boil, carefully add the chicken breasts ensuring they are fully submerged.
Place the lid slightly offset so a little steam can escape and let the chicken gently poach for about 25 minutes.
Once the chicken is fully cooked, transfer it to a cutting board and let it rest while while finishing the soup.
Reduce the heat to medium-low and slowly stir in the heavy cream.
While the soup comes back up to a low simmer, whisk together the flour, baking powder, and black pepper in a mixing bowl.
Fold in the buttermilk and egg.
Once the dough begins coming together, fold in the melted butter. Stop mixing once all of the dry flour disappears and dough ball has formed.
Cube the cooked chicken into bite-sized pieces and return it to the soup.
Pinch off pieces of the dumpling dough, gently roll them into balls, and drop them directly into the simmering soup.
Give everything a gentle stir, reduce the heat to medium-low, partially cover the pot, and let the dumplings cook for about five minutes.
Once they’ve started puffing up and floating, give them one more gentle stir, cover the pot completely, and continue cooking for another twenty minutes.
Serve your chicken and dumplings hot, topped with a little freshly chopped basil for a fresh pop of color and flavor.