This is the first time I've actually ate our rhubarb, despite the fact it came with our house.  I always freeze it intending to use it later only for it to get lost in the freezer.  I derived this recipe from America's Test Kitchen's peach crisp recipe.  I reduced the sugar content  and gave an all natural no sugar option with stevia, replaced coconut oil for butter, added flax meal, buckwheat or almond flour, and oatmeal in place of all purpose flour, and I added flour to the fruit mixture, because I felt it was too watery without it.  So not too bad for a dessert!  Low or no added sugar, good fat, nuts, and low to no gluten.
Strawberry and Rhubarb Crisp (no flour)

Ingredients

Filling
4-5 rhubarb  stalks
about 1 lb organic strawberries washed cored and cut in half
1 tsp stevia (or 1 tablespoon of organic sugar)
1 tablespoon lemon juice
1 tablespoon organic (so it's not GMO) corn starch

Topping
1/2 cup of buckwheat flour or almond flour/ or meal
2 tablespoon of ground flax
1/2 cup of instant rolled oat (can sub almond meal if you can't have gluten or want to make it paleo)
2 tablespoons of brown sugar (or 1 1/2 tsp of stevia)
1/4 teaspoon pink salt
1/3 cup of coconut oil
1 cup of chopped pecan, walnuts, or almonds

Instructions

1. FOR THE TOPPING: pulse the flour, sugar, coconut oil, salt, and nuts in a food processor and store in the fridge.
2. FOR THE FILING: Adjust an oven rack to the lower-middle position and heat the oven to 350 degrees.  Combine the strawberries, rhubarb, sugar, juice, and flour in a large bowl and toss to combine.  Transfer the mixture to a 9 inch glass pie plate, place the pie plate on a rimmed baking sheet, and sprinkle the chilled topping evenly over the top.  
3. Bake for 40-45 min.  Bake until the topping is golden brown.  Serve warm.