Preheat Oven to 375 F
Prepare Topping:
Grate cold butter into a bowl with a cheese grater.
Add sugars, flour, cinnamon and salt.
Use a pasty cutter, or two butter knives, to combine. Do not over mix. Allow for clumps to form.
Make Filling:
Wash and chop rhubarb into 2 inch pieces. Slice clean strawberries.
In a bowl combine strawberries and rhubarb with sugars. Let mixture sit for about 10 min. This allows the excess liquid to drain off your fruit. Drain off liquid and add corn starch, salt, orange juice and vanilla. Mix until fruit is covered and pour over a prepared crust or into a 8x8 baking dish for a crumble.
Top with crumble and bake at 375 for 20 min. Tent with foil, lower temp to 350 and continue baking for an additional 20 min.
Remove from oven and let cool before serving.
Garnish with fresh berries and serve warm with vanilla ice cream.