Heat oil in a large saucepan over medium-high.
Cook the wings until golden brown-about 10 minutes turning a few times.
Add onion, carrot, and celery until everything is deeply browned, 15 more mins.
Add rosemary for a minute.
Add wine.
Bring to a boil and reduce wine by half, about 5 mins.
Add stock and bring it up to a boil. Reduce to a simmer, stirring a few times occasionally.
Reduce liquid by 1/3 for about 30-35 mins.
Strain the stock (you should get 4 cups-if not add extra stock)
Next, make roux:
In a medium saucepan on medium heat, melt the butter.
Whisk in wondra and cook while stirring 4 mins.
Add in your stock slowly and whisking between each addition.
Reduce while on a simmer to 3 cups-should take 10 mins.
Season with salt and pepper.