DW got a large bamboo cutting board and then got 4 round shower curtain end pieces from Walmart and glued them on the bottom to conform with the metal rack over the stove burners. They can also be screwed on. Makes for a nice, tight custom fit and can be easily lifted off to use the burners. It did necessitate removing the folding metal cover, but that only involved removing two screws. Cover was a flimsy piece of junk, anyway.
We got a new camper with a different rack pattern over the burners, but only had to remove and reposition the "feet" on the bottom of the board.
I posted some photos of it on here once but now can't find the posting or the original photos. Maybe a search will reveal them, but I haven't been able to find it.
This more than doubled her counter space in the Surveyor 220. Best mod we've ever done.
2013 Surveyor SP220
2010 Silverado LT 5.3 V8
The world is a great book, of which those who never stir from home
read only a page. - St. Augustine