Combine chopped rhubarb and strawberries in a saucepan. Cover with water. Bring to a boil and simmer for 8-10 minutes.
Drain rhubarb-strawberry mixture (save the juice) and return the mash to a blender to blend smooth.
In the same saucepan, heat 2 tablespoons of olive oil and cook onions until translucent, 4-5 minutes. Add all remaining ingredients and rhubarb-strawberry mash. Simmer for 35-40 minutes. Brush onto meat of your choice and enjoy!
*** Because of the vinegar in the recipe, you could definitely can it! Ladle into mason jars, leaving 1/2 inch headspace at the top. Clean jar rim and scew lid and band on. Place jars in a water canner and bring to a boil. Process for 15 minutes. Remove from water and cool completely before storing.