Over medium-high heat, add butter, diced celery, and carrots to a sizable stockpot. 3 minutes of sauteing. Cook the garlic for 30 more seconds after adding it.

Add chicken stock and season the soup with salt, pepper, crushed red pepper, rosemary, sage, and crushed red pepper before tasting it. When necessary, taste and add "better than bullion" chicken bouillon cubes or granules.

Boiling the broth. Add the noodles and cook them just until they are al dente, using either dry store-bought pasta or uncooked homemade egg noodles.

Be careful not to overcook store-bought noodles if using them! Once they are just barely soft, turn off the heat. You don't want the noodles to become mushy since they will continue to cook once the heat is turned off.

Chicken from the rotisserie chicken should be added. Once more tasting the soup, adjust the seasoning as desired.

Depending on how fresh your chicken was, keep leftovers in an airtight jar in the fridge for 4-5 days.