Wipe on Poly is my go-to! Make sure you choose the 'satin' because glossy will look bad. It's quite easy to use. Here's how I do it :

1. sand the wood to 220 (you might do 120 first then 220)
2. lightly moisten the wood to raise the fibers
3. sand again with 220
4. Now you can wipe on the poly. Wear gloves, and use a paper towel or a foam brush to wipe on a VERY THIN coat all over.
5. allow to dry inside (doesn't dry great if it's too cold), which should only take 2 hours or so
6. LIGHTLY sand again with 220. Just a little. Don't remove the layer, just touch it a little.
7. Do a second light coat just the same
8. Lightly sand again
9. Third coat. No need to sand this time.

If you get all the surfaces that's good because then the wood is impervious to moisture and will not be able to warp. This coating is also water-resistant to spills. One thing Is that the lid always sticks to the bottle with this brand and can be hard to remove. Another user here has suggested to me using vaseline on the threads of the lid. IDK. I always have to use tools to get the dang lid off.

Post pics when you're done! We would love to see it.

I use clear matte Polycrylic on lighter woods, like maple. I find more glossy variants to have a plastic-y feel.

I recently started using Hassui ceramic coating on anything that needs to be food safe or water resistant. More expensive, but it leaves it feeling like natural wood and beads water

This is what I like:

1. Sand to at least 220
2. Apply 1x coat of spray shellac and let it sit 30 mins
3. Gently scuff surface w/ sandpaper and wipe clean
4. repeat steps 2 & 3 two more times
5. Apply a wax (paste wax is fine) and burnish in with double-zero steel wool
6. Let the wax sit a few minutes then wipe it off
7. repeat steps 5 and 6 until you’ve got the finish you want

Ends up with a very soft-to-the-touch finish that’s matte and not shiny.

I did this on a coffee table that gets heavy use and I’ll only probably need to reapply wax once a year. A shelf should need zero maintenance.

I like Rubio monocoat. It’s a two part catalyzed finish but is applied like a rub on poly. I used it for a walnut bathroom counter and it has held up well. https://www.rubiomonocoatusa.com/?country=us&reset