If using garden rhubarb, cut off leaves and stem ends.Wash thoroughly with water then pat dry. Slice rhubarb in ½-1 inch pieces. Whole rhubarb stalks may also be frozen.
Line a baking sheet with parchment paper. Spread sliced rhubarb in a single layer. Freeze overnight or until firm.
Once frozen, transfer rhubarb to a vacuum-sealed bag. Vacuum seal your bag using a vacuum sealer machine. Label with product, date, and amount. Freeze until ready to use.