rhubarb crisp

Took this to a neighborhood potluck last night and it received very high reviews.  Like: silence as we all consumed it, and then a "wow, this is good."  I got the gist of it from here but then cut sugar and added cardamom.  And no, I do not like strawberries with rhubarb.  LET RHUBARB SHINE.  The real trick is to use freshly cut rhubarb.  What isn't good when fresh?  Why do we insist on eating produce out of season? 

Ingredients & Instructions
Preheat oven to 375.

Mix these up and put in baking container (I used 1.8 L baking dish plus a loaf pan)
6 cups of rhubarb (or so) washed and chopped
1/3-1/2 c. sugar
3 T flour
1 tsp. cardamom

Then mix these together, cutting butter in with a fork and then fingers, and then put over rhubarb
3/4 c. rolled oats (or more if there's more rhubarb)
1/3-1/2 c. brown sugar
6 T flour
1/2 tsp. cinnamon
6 T butter
(would also probably good with nuts)

Bake 35 minutes (top golden, rhubarb tender, and a bubbly cauldron of goodness).  Let it sit at least 10 minutes and it will thicken up.

Excellent with vanilla ice cream (which adds more sweetness so sugar can be cut) or yogurt.