How to stain a island top?

Hi Karen, yes I would definitely sand it down first. Depending on how old the butcher block is over time just people's hands alone (whether just washed or not) leave oils behind that will block the wood from being able to evenly absorbs the stain. Fine grit will probably work fine just do a nice thorough sanding job over the entire thing then clean thoroughly before staining.

You can stain the top but you will need to sand it down to bare wood. Make sure you use food safe products for the stain and the topcoat.

Hope this helps!

https://www.thriftydecorchick.com/2017/12/how-to-finish-and-protect-wood-counters.html

Thank you!