Hole in the wall

[Shanmpo]

Hello!
I have torn down a wall between the kitchen and the dining room and put up a glulam beam. I will then put renovation plasterboard on the walls. Now there is a hole in the wall where the support post stands. There's a difference of about 1 cm between one wall and the post. How would you cover this in the nicest way?

Thanks in advance!

 

[Stefan N]

Some strips of masonite before the plasterboard will be good.