Make the Dumplings: In a large mixing bowl, 2 1/4 cups flour, baking powder and salt. Stir to combine. Add butter and shortening and cut in with a fork or pastry blender. 

Add buttermilk and egg, mixing with a dough whisk or wooden spoon. Add additional flour 2 tablespoons at a time until dough forms a ball and pulls away from the bowl. 

Lightly flour a clean surface and place the dumpling dough over the flour. Use a rolling pin to roll out to 1/4 inch thickness, adding more flour as needed. 

Use a pizza cutter to cut into 1 inch wide strips, then cut cross-wise to make dumplings about 2 inches long. 

Dice onions and celery, slice carrots and coarsely chop or shred the chicken. We are using both chicken breasts from a whole chicken. Dark meat works well also or a combination of both.

In a large dutch oven or large soup pan, add the olive oil and vegetables. Cook over medium-high heat, stirring occasionally until vegetables are softened. 

Stir in the chicken broth and bring to a low boil. 

Drop dumplings into the boiling chicken stock a few at a time, stirring occasionally. Cook dumplings about 5 minutes until they start to puff up. 

Stir in chicken, garlic, thyme, pepper and salt. Lower to simmer and stir in the milk. 

Continue to cook until dumplings are cooked through. You can cut a dumpling in half to make sure they are fluffy not doughy. 

Remove from heat and serve immediately.