What is the best product to use to cover and smooth a 2' by 4' area of popcorn ceiling, rather than remove it?

Area is a 2'W X 4'L X 2'D recess in bathroom over sink with a light fixture. It has popcorn and building was built in 1969 so may have asbestos. Rather than going through the dangerousness of removing it I want to fill it in to smooth it. What would be the best product to use? I did get a spray can of popcorn ceiling texture that says it can smoothed to fine texture while still wet.