One of the most popular cakes we make at Flour is our Lemon-Raspberry Cake: lemon pound cake, crushed raspberries, lemon curd, buttercream. To give the raspberry layer extra flavor, we soak whole raspberries in a vanilla syrup for several hours and then strain and crush the berries. The happy by product of this raspberry soaking is vanilla-and-raspberry-infused syrup. When we first opened, I knew I wanted to make something special with the syrup. I’d read about the shrub, a sweetened raspberry vinegar drink that was popular in colonial times, and thought that it could be a fun drink to offer at Flour. I mixed some of the syrup with raspberry vinegar and then added soda water. Blech! It was awful. I almost gave up on the idea. Then I tried the raspberry syrup with lemon and lime juice and a star was born.
This drink has legions of addicts among Flour followers. We sell so many that we can no longer rely on the leftover raspberry syrup to keep us stocked; we now make the syrup from scratch just to keep up with demand. The syrup stores great in the fridge or freezer, so make a batch to keep on hand for when the raspberry seltzer urge hits. Trust me, it will.
- Yield: 1 ¾ cups (420 ml) raspberry syrup (enough for about 9 drinks)
- 1 cup (130 g) fresh or frozen raspberries
- 1 cup (200 g) vanilla sugar
- 2 tbsp freshly squeezed lemon juice
- 1 tbsp freshly squeezed lime juice
- 1¼ cups (300 ml) soda water for each drink
- In a small saucepan, combine the raspberries, vanilla sugar, and 1 cup (240 ml) water and bring to a boil over high heat, stirring until the sugar has dissolved. Remove from the heat and let steep for 1 hour
- Transfer the raspberry mixture to the blender and purée. Strain through the sieve placed over a small bowl to remove most of the raspberry seeds. Add the lemon and lime juices to the raspberry syrup and stir to combine. (The syrup can be stored in an airtight container in the fridge for up to 2 weeks or in the freezer for up to 3 months.)
- For each drink, put 3 tbsp syrup in the bottom of a tall glass, fill the glass with ice, and then pour in 1¼ cups (300 ml) soda water. Using a long spoon, stir until well mixed, then serve.