Peel rhubarb,if it becomes stringy when slicing. Make sure to rinse berries and rhubarb well with cool water prior to use.
Place honey, butter and vanilla over medium heat. Stir occasionally until butter melts and mixture comes to a light boil.
Add rhubarb. Stir frequently, keep at medium heat for 3-4 minutes until rhubarb cooks down.
After 3-4 minutes, add berries. Continue at medium heat for another 3-4 minutes Stir frequently. Some of the raspberries will cook down.
Once the time is complete sauce should look like this.
Place in airtight container and refrigerate until cold. You can use it warm but I prefer it cold.
Once sauce is chilled ( 6-8 hours) try some in plain yogurt or on whipped cream! Yum!