Heat the olive oil in a large saucepan over medium-high heat until shimmering.

Season the chicken chunks with 1/4 teaspoon salt and pepper, then add to the pan. Cook for about 2 minutes, just until the chicken is no longer pink on the outside. Remove the chicken with a slotted spoon and set aside, leaving behind the oil.

Add the butternut squash, celery, and onion to the pan. Sauté for 5 minutes, stirring occasionally, until the onion softens and the squash begins to tenderize.

Pour in the chicken broth, add the dill sprigs, and stir in 3 cups of water. Bring the mixture to a boil, then reduce to a steady simmer. Cook for 15 minutes, or until you can pierce the squash easily with a knife.

While the vegetables cook, prepare the dumpling dough. In a small bowl, whisk together the white whole wheat flour, baking soda, 1/4 teaspoon salt, and 1/8 teaspoon pepper. Use your fingertips to work the cold butter into the flour until the mixture forms coarse crumbs.

Add the milk to the dry mixture and stir gently until a soft dough forms. Be careful not to overmix.

Return the chicken to the broth along with the thawed peas. Let everything simmer together for a few minutes to heat through.

Drop the dumpling dough by teaspoons into the simmering broth, ensuring the dumplings are evenly spaced. Cover the pot and cook for 5 minutes without lifting the lid.

Uncover and continue simmering for another 3 minutes, or until the dumplings are fully cooked through. They should be light and fluffy!

Discard the dill sprigs, sprinkle the stew with fresh chopped dill, and serve immediately.