Deglazing. Follow to soup post
Deglaze your chicken pan for free stock.
Use a heavy gauge pan to bake your chicken or turkey. We are not talking skinless/boneless here, but dark (cheap) meat. If you use a sugar-containing chicken baste, don't put it on till the last 20 min of cooking, to avoid burnt sugar on the bottom of the pan.
Eat chix and don't wash the pan. Pour off excess grease for later use or discard. OK, if immunocompromised you can store your pan in the fridge overnight, but I just leave it in the oven.
Roast your vegetables as the original poster suggests, using the same pan, not washed. You can even use the chicken grease from the previous night.
Remove veg from pan, add about 1/3 inch of water to cover the stuff stuck to the bottom. Add seasonings of your choice.
Simmer on the stove top about 1/2 hour. Use an implement to scrape the stuff off of the bottom of the pan and encourage it to re-suspend.
That's it. Stock should be toasty brown.