1. Cut off wing tips; cut each wing in half at the joint. Warm oil in pot over medium-high heat. Add wings; season with salt and pepper. Cook, turning often, until lightly browned, about 10 minutes.
2. Sprinkle flour over wings; reduce heat slightly. Stir well. Sauté for 2 minutes (pan will be dry). Pour in broth and lager. Increase heat to high; bring to a boil, stirring to pick up any browned bits. Reduce heat to medium and simmer, partially covered, until slightly thickened, about 1 hour.
3. Strain mixture, discarding wings. Return gravy to pot; bring to a boil over high heat. Season with salt and pepper. Serve or let cool, cover and chill. (Can be made up to 3 days in advance. Keep covered and refrigerated. Rewarm over low heat just before serving.)