From: Everyday Food (Martha Stewart)
I combined the fresh rhubarb from the farm share with some rhubarb I had in the freezer from last year's farm share (why didn't I use that earlier?) and made this recipe. It was nice to find a recipe that just used rhubarb without requiring a complementary fruit. I subbed Splenda for all of the sugar in this recipe and it worked well. It came together very quickly, especially since I didn't use the food processor and just mixed the topping by hand in a bowl. I have eaten it both for dessert and for breakfast this week.
2 pounds rhubarb
1 1/2 cups sugar (I used Splenda)
1/4 cup flour
1/2 cup (1 stick) butter, chilled, cut into pieces
1 cup rolled oats
1/2 tsp cinnamon
Preheat oven to 400 degrees. Slice the rhubarb into uniform 3/4 inch pieces. Place in a 9x13 baking dish; toss with 1 cup of the sugar and 1/4 cup of the flour.
In a food processor (I just used my fingers and mixed the ingredients in a bowl because I didn't feel like hauling out the mixer for this), pulse the remaining 1/2 cup flour with the butter until the clumps are pea-sized. Add the remaining 1/2 cup of sugar, rolled oats, and cinnamon. Pulse just to combine. Sprinkle over the rhubarb.
Bake until the rhubarb is tender and the topping is golden, approx 35 minutes.