4heaped tablespoons xylitolor to taste, can be also sweetened with sugar
Wash the rhubarb and cut into approx. 3 cm /1-inch pieces, slightly crush cardamom capsules (only to open them), squeeze the juice from 1 small orange, ½ lemon and cut off a large piece of the orange skin.
Add all ingredients into a large pot, sweeten to taste with xylitol/sugar, bring to a boil over medium heat, then simmer for a couple of minutes until the rhubarb is soft and begins to fall apart.
Take the pot off the heat and allow to stand for approx. 30 minutes (optional), then strain through a mesh strainer, squeezing as much liquid from the rhubarb as possible.
The lemonade can be served warm or cold, with ice cubes.
The lemonade will keep up in the fridge for up to 3 days (but don’t forget to strain it and discard the cooked rhubarb).