If working in the roasting tray, skim off any excess fat/grease from the drippings and discard.
Place the tray over medium heat.
Add in all-purpose flour and whisk with the drippings.
Pour in broth and continue whisking, loosening all the dark bits.
Carefully transfer the entire mixture into a small saucepan and continue to whisk over medium heat until the mixture bubbles, and becomes slightly thickened and smooth, about 3-5 minutes.
Season with salt and pepper to your taste.
Optional: add fresh chopped herbs and aromatics.
Remove from heat and serve.
Notes
If you have not much pan drippings you can start with 1 tablespoon of flour and adjust accordingly.