1-First, prepare all ingredients: dice the onion, slice carrots, chop celery, shred the cooked chicken, and measure out the broth and milk. In a large pot, melt 1 tablespoon unsalted butter over medium heat; then add 3/4 cup chopped yellow onion, 1 cup sliced or diced carrots, 1 cup sliced or diced celery, and 2 garlic cloves, minced. Cook, stirring occasionally, for 5 minutes until the vegetables soften, then stir in 1/4 cup all-purpose flour, 1/2 teaspoon salt, 1/2 teaspoon fresh ground pepper, 1 teaspoon dried thyme leaves (or 2 teaspoons fresh), and 1/2 teaspoon dried oregano (or 1 teaspoon fresh), and cook for 2 more minutes.

2-Next, add 8 cups chicken broth and 1 medium peeled and diced potato (about 1 and 1/2 cups), stir, then bring to a boil for 3 minutes. Reduce heat to medium-low, partially cover, and simmer for 25 minutes until the potatoes are tender. Taste and adjust seasoning at this point to make sure it suits your taste.

3-Finally, add 2 cups shredded or chopped cooked chicken, 1 cup half-and-half or whole milk, and 3 to 4 cups uncooked wide egg noodles. Cook for 10 minutes or until the noodles are tender and the soup has thickened. Taste and adjust seasoning before serving warm this step ensures everything blends perfectly.