Heat the water and sugar in a saucepan on medium heat until the sugar dissolves. Add the rhubarb and bring to a boil. Cook for 15 minutes until the rhubarb is tender. Puree with an immersion blender, until it’s as smooth or chunky as you want. Cool.
In a bowl, whisk together the Greek yogurt, half & half, sugar, and vanilla. Chill for a few hours or overnight, to allow the rhubarb to infuse throughout the yogurt mixture.
Stir the strawberries into the yogurt mixture.
Add to your ice-cream maker and follow the directions to churn the ice-cream. With mine, I start it churning for a couple minutes and then layer on the ice and rock salt. It’s easy to know when it’s done because it just stops.
After the ice-cream is done churning, put into freezer safe containers and freeze until hard enough to scoop, about 2 hours. Enjoy!
Note: Depending on your type of ice-cream maker, you might want to chill the yogurt mixture in the freezer for a half hour or so before churning. Also it might want you to add the strawberries toward the end of churning. Follow the directions for your ice-cream maker.