Preheat the oven to 350. Line a 9x13 pan with parchment paper.
Process the ingredients for the crust in a food processor until they come together in a ball. Spread in the bottom of the prepared pan.
Combine the rhubarb and sweetener in a medium skillet. Cook over medium heat for 5 minutes until the rhubarb is beginning to soften. Add the strawberries and cook an additional 2-3 minutes. Add the xanthan gum and mix well. Cool for at least 10 minutes.
Spread the rhubarb mixture on top of the crust.
Add the crumble ingredients to the food processor. Pulse until large crumbs form. Sprinkle on top of the filling.
Bake for 40 minutes until golden brown.
Notes
Nutrition: This recipe makes 18 bars. The nutrition facts are for 1 bar. There are 5.5 NET carbs per serving.To Store: The bars should be kept airtight and refrigerated except for when you are serving. They will last 4-5 days. To Freeze: Place in a freezer-safe container, and they will last in the freezer for 1-2 months. Notes on Sweeteners:
I use my own blend of xylitol, erythritol, and stevia in my recipes. This is twice as sweet as sugar. It is comparable to Trim Healthy Mama Gentle Sweet and Truvia.
To sub in Swerve or Lakanto Monk Fruit use 1.5 times the amount of sweetener called for.
To sub in Pyure or Trim Healthy Mama Super Sweet use half the amount of sweetener called for.
Substitutions will work in most recipes. They may not work in candies, such as caramel.