¼cupfreshly squeezed orange juice (about 1 orange)
1tbspCointreau or Grand Marnier(optional, helps keep gelato at a softer texture even when fully frozen)
For the gelato base: Make the gelato base of your choice, then strain it into an airtight container. Cool to room temperature, then refrigerate overnight. The gelato base must be very cold before churning: this will produce the smoothest, silkiest texture.
For the rhubarb compote: In a saucepan, combine the rhubarb, sugar, orange juice and zest, and Cointreau or Grand-Marnier. Bring to a boil, lower the heat, and simmer, stirring from time to time, until the rhubarb is very soft, about 10 minutes. Remove from the heat. Blend to a very smooth consistency using a stand blender or stick blender. Let cool to room temperature, then refrigerate until completely cool.
To churn the rhubarb gelato: Fish the vanilla bean out of the gelato base.Whisk the rhubarb compote into the cold gelato base. Pour into the bowl of an ice cream maker and churn according to the manufacturer's instructions. Stop the machine when the gelato is icy but still soft.
STORAGE: Transfer the rhubarb gelato to an airtight container and freeze until firm, about two hours.Rhubarb gelato is at its creamiest and best if enjoyed within 2 weeks. Past that, some ice crystals will inevitably start forming (especially if the gelato is kept in the freezer section of a regular fridge, as opposed to a chest freezer) and the texture won't be quite as smooth. The gelato will still be perfectly edible for up to 2 months, but my advice is: enjoy it as quickly as possible after churning.
SERVING: Always take rhubarb gelato out to room temperature 20 minutes before serving to make it easier to scoop. This will also allow you to enjoy the treat at its ideal temperature and texture.
COLOR NOTE: To achieve a blush pink color, you need to select the "pinkest" parts of rhubarb stalks. If using whole stalks, the color gelato might be more beige than pink, but you can add a drop or two of pink food coloring to give the shade a little nudge.
MAKE IT DAIRY FREE: When making the gelato base, substitute lactose-free milk or oat milk for the regular milk, and lactose-free heavy cream or soy cream for the regular heavy cream.