Cut the rhubarb into 6cm long pieces, and place into a bowl and toss with the sugar, and salt.
Turn the dough out onto a lightly floured surface and roll into a circle turning the dough often to keep it as circulars possible. Transfer to a sheet pan lined with parchment paper.
Arrange the rhubarb inside the crust, leaving about a 2” border around the edges, which will be what you fold over. Sprinkle any excess sugar mixture over the rhubarb.
Fold the edges over the rhubarb to encloseit, folding the pie dough over onto itself. Secure with a little egg wash.
Place the galette in the fridge to chill.Meanwhile, heat the oven to 200°c.
Egg wash the galette crust. Bake the galette in the lower section of the oven for 35-40 minutes or until the crust is golden brown.
Remove from the oven and allow to cool on the baking sheet before serving.