Price: $13

Ingredients: Black barrel rum, rhubarb soda and buttermilk orange sherbet, plus a bit of nutmeg sprinkled on the frothy top

Inspiration: Birthday parties! “I really loved fruit punch with sherbet in it, and I wanted to recreate that feeling in a drink,” says Catalyst bar manager Curtis Hancock. And with the housemade soda, the Maine native taps another childhood memory: chomping on rhubarb from his parents’ garden. “I would snack on it like celery.” Hancock also taps his pre-bartending time spent in the kitchen of a Napa restaurant, here adapting a previous lemon sherbet recipe for a less tart version made with help from pastry chef Nicole Boutin.

Taste: Light, refreshing, makes you wish you were sitting poolside. Remind yourself every few sips that there is booze in this.

Garden Variety: Rhubarb not your jam? Try the Untitled ($13), a sweet, herbaceous take on Moroccan mint tea, a beverage Hancock often enjoys at home. “During the summertime, I grow a lot of mint.”

The next round: Other newcomers on the spring menu range from a sparkling rosé cocktail to the Tech Square Cooler, which Hancock says offers a good introduction to mezcal. The smoky-yet-sweet cocktail features pineapple juice with a touch of soda and Cassis. “It’s really refreshing but still packs a lot of flavor.”

Catalyst 300 Technology Square, Cambridge (617-576-3000) catalystrestaurant.com