Super fast Cast iron Gluten Free Sour Cherry rhubarb Crumble

Super fast Gluten Free Sour Cherry Crumble
INGREDIENTS

1 cup sour cherry(pitted but not necessary watch your teeth)
1 lb of rhubarb
Monk fruit liquid or powder to your sweetness liking I used 20 drops or 1/4 cup powder
1 tsp Cinnamon (Ground)
1 cup walnut pieces
3/4 cup of almond flour
1 tsp vanilla
1/3 cup Butter (Unsalted, cut up into about 8 pieces)

Cook down all ingredients except cherries, add them in at the end