I made this on Leela's request. I used a 9x13 pan and added more strawberry and rhubarb. I probably should have added more topping, but overall, Leela and I enjoyed it.
https://www.faithfullyglutenfree.com/rhubarb-crisp/
I made this rhubarb cake using Bob's Red Mill 1:1 flour. I really liked it because it wasn't too sweet
https://northwildkitchen.com/simple-norwegian-rhubarb-cake-rabarbrakake/#/