Preheat oven to 350 degrees.

Grease or put liners in a muffin tin (liners are so much easier to clean up). Set aside.

Whisk together gluten free flour, xanthan gum, baking powder, baking soda and sea salt in a mixing bowl. Set aside.

In the bowl of your stand mixer add butter, coconut oil, eggs, sugar, milk and vanilla. Blend until smooth. Add the dry ingredients and blend together. Add the rhubarb and strawberries. Blend until combined. Do not over blend! You do not want to break up the rhubarb or make the strawberries mushy.

Divide muffin dough between all twelve muffin cups. Set aside.

In a mixing bowl add gluten free rolled oats, brown rice flour, brown sugar, sea salt, melted butter and sliced almonds. Stir until a crumble forms. 

Spoon the crumbly streusel over the muffin dough. Press the streusel into the muffins and add a bit more until all the streusel has been completely used.

Bake at 350 degrees for 30-33 minutes or until the streusel is browned and the muffins are done.

Let the muffins cool completely before storing in an airtight container.