Yesterday's Gravy Tonight's Soup

I don't know why I've never thought of it before. Gravy -- especially the cream gravy I make for fried chicken -- is basically a roux. Sometimes I thicken soup with a roux. Today I thickened our soup with gravy.
First I sautéed carrots, onions, celery and after a couple minutes a bit of chopped garlic in olive oil. When those vegetables softened up I added in sliced mushrooms, about 3 quarts of chicken broth, chopped turkey (I had that in the freezer) and some of the leftover chicken (without the skin) and a heavy half cup gravy. The soup came up to a boil and then simmered for about 10 minutes, One disappointment -- no egg noodles in the house. Cooked in the creamy savory broth they would have been delicious. Instead I grabbed the last of a bag of penne and tossed them in (pre-cooked) for a creamy noodle soup dinner.