Combine turkey necks, water, onions and bay leaves. (If using store-bought broth, skip to step 3.)
Bring to a boil. Lower to a simmer. Add salt and pepper to taste and boil for at least 1 hour, up to 3 hours. During cooking, skim any impurities from the surface. Strain.
Combine broth and potatoes. Bring to a low simmer for 20 minutes, until potatoes are fork tender.
Add remaining vegetables, rosemary, and egg noodles.
Simmer for 15 minutes until noodles are cooked through and vegetables are tender.
Add turkey and remove rosemary.
Remove 1 cup of soup and blend with a hand blender. Add back to soup to make it a little creamy.
This soup freezes well and can be heated up for an easy weeknight meal. Batch up by doubling the recipe, or freeze any leftovers in family sized portions in an airtight container. This soup tastes great with a variety of vegetables. Use up any leftover veggies by adding into the soup at the end.