Following on from my workbench video, this is how I was able to flatten or surface the using a router and a simple sled made from plywood.

Using a hand plane is a more traditional approach to this but hand planes aren't cheap and I don't own any yet. Further more, I made a pretty rough job of the original glue up which would have made hand planning very hard indeed!

The specific router bit I used:
https://www.carbatec.co.nz/product/19...

Similar bits from Amazon that should do the same job
https://amzn.to/3qUB28n
https://amzn.to/3uUaxkZ

Some of my tools:
Pocket hole jig - https://amzn.to/3DxARVG
Woodpeckers stainless steel squares - https://www.woodpeck.com/woodpeckers-...
Planer/Thicknesser - https://www.carbatec.co.nz/product/36...
Cabinet Saw - https://www.carbatec.co.nz/product/17...
Jig Saw - https://amzn.to/3j0Eom8
Circular Saw - https://amzn.to/3v9Nrab
Brad point bits - https://amzn.to/3K6rnmK and https://amzn.to/3x7uAie
Right angle clamps - https://amzn.to/3uP9zX8