I attempted my first Souffle last night (a simple cheese souffle) and it ended up being a complete disaster. The outside puffed out, but once you removed the top crust, it was entirely hollow on the inside.
I'm familiar with reading other recipes that souffles can "collapse", primarily due to not getting enough air into the egg whites or incorporating the egg yolk mixture too thoroughly and working out the air. However, this isn't exactly what happened.
I put in an instant read thermometer as I was taking the souffles out, and saw that the internal temperature was over 200F (note: I had put them in at 390F for approximately 20 minutes in 7oz ramekins). Knowing that the whites and yolks denature at different temperatures, I'm guessing I want to denature the whites, but still leave the yolks soft, which puts me at a target temperature of 151-152F-ish.
Clearly the temperature is a major issue, but could there be something else I am overlooking? What should the internal temperature be for a souffle? I appreciate everyone's help!