1. In a large Dutch oven or pot, heat the butter over medium-low heat.
2. Once melted, add the chopped onion, carrots, and celery.
3. Cook for 6 to 8 minutes, stirring every minute or so, until soft and wilted.
4. In the last 30 seconds, add the minced garlic and stir to combine.
5. Add the flour and mix until all the vegetables are coated.
6. Let the flour cook for 1 minute.
7. Add the chicken stock, milk, potatoes, salt, pepper, and thyme.
8. Stir to combine.
9. Bring the pot to a boil, then reduce the heat.
10. Simmer for 15 to 20 minutes, until the potatoes are fork-tender.
11. Stir every 4 minutes or so to make sure nothing sticks to the bottom of the pot.
12. Add the cooked shredded chicken, frozen peas, parsley, and optional chopped spinach.
13. Simmer for 5 more minutes.
14. Carefully taste and adjust the seasoning to your liking.
15. Remove from the heat and serve with a homemade biscuit, garlic bread, or buttery toasted bread if desired.

Optional Uncooked Chicken Method

If using uncooked chicken breasts, cut 2 chicken breasts into small bite-sized pieces.

Add them to the heated pan between the butter step and the vegetable step.

Cook for 6 to 7 minutes, until the chicken is no longer pink.

Add the flour and continue with the recipe.

Storage and Reheating

Store leftovers in airtight containers in the refrigerator for up to 4 to 5 days.

Freeze in freezer-safe containers for up to 3 months.

Defrost overnight in the refrigerator before reheating.

Reheat on the stovetop over medium-low heat after defrosting.

For best results, reheat on the stovetop over medium heat until warm.

The soup can also be defrosted directly on the stovetop, but it takes longer.

If in a rush, reheat in the microwave in 30-second increments. Cover the bowl with a damp paper towel when microwaving.