I have a candy thermometer and heated the egg whites and sugar to 160. I have a stand mixer and mixed on high FOREVER until stiff peaks formed. I added butter at ROOM TEMP 1 pat at a time and beat for 10 seconds after each addition. And now, the frosting looks like SOUP! I read that you need to be patient and keep mixing in the stand mixer until it comes back together, but I have been mixing it for over HALF AN HOUR and it still is soup.
Please help and suggest what I am doing wrong!! Is it possible that the butter was too soft? (it wasn't melted, but veeerry soft). Does anyone have a fool proof recipe? I have tried TWO different recipes. The last one was eight egg whites, 1 1/2 cup sugar and 2 sticks of butter.