I use this stuff: https://www.amazon.com/dp/B0044SAXKQ/I like it because it comes in a block so it gives me the effect of stretched paper without having to stretch it, lol. And so smooth. Hot press. A lot of people recommend cold press and I really don't know why. Maybe theres is a smoother cold press than I've found.
It's quite smooth even though they say it's cold press. Watercolor is more permanent on this paper which can be a good thing and a bad thing.