Apparently its National Pisco Sour Day in Peru 1st February
I discovered this only today on the fb would you believe.
It reminded me of my time in Peru a couple of years back , I loved the Pisco Sour and had many when I was in Lima
Here is the last one I tasted in the airport on the way back.
The top is whisked egg white with a dash of Angostura bitters.
The best Pisco Sour I had in Lima was at Huaca Pucllana a lovely bar at the historical site with my friends Javier and Ronald who runs Lima Walks