Start by melting the butter in a large stockpot over medium-high heat. Toss in the diced celery and carrots, sautéing them for about 3 minutes until they begin to soften. Add the minced garlic, allowing it to cook for another 30 seconds until fragrant and aromatic.
Pour in the chicken stock, infusing it with the dried rosemary, sage, crushed red pepper flakes, salt, and pepper. Stir in a spoonful of "Better Than Bouillon" chicken base or chicken bouillon granules, adjusting the amount to achieve a rich, flavorful broth.
Bring the broth to a vigorous boil. Carefully add the noodles—whether homemade or store-bought—and cook until they reach al dente. If you're using dry pasta, be sure to monitor closely to avoid overcooking. Once the noodles are just tender, remove the pot from the heat, as they will continue to soften in the residual warmth.
Gently fold in the shredded rotisserie chicken, stirring until everything is well-combined. Taste the broth one more time and adjust the seasoning as needed.
Store any leftovers in an airtight container and refrigerate for 4-5 days, depending on the freshness of the chicken.
