They knew about this in the middle ages too. There is a recipe by Martino (somewhat plagiarised but surprisingly improved upon by Platina) which is basically roast lamb stuffed with rosemary, garlic and olive oil all smashed up together. Then you take more garlic and rosemary and verjuice and egg yolks and as the lamb cooks you pour the juices into this sauce and then use it to baste the lamb. Then when the lamb is done you make the sauce into, well, a sauce and it is very, very, very good.

I once cooked for a feast where we planned for 80 and only 45 showed up. This was the only dish that didn't come back to the kitchen half eaten. This and the gnocchi actually....