like using blood oranges for the deep rich orange color. Seville oranges work well for their deep floral zest. I’ve also used Cava oranges, which are lighter and have a bit of a grapefruit brightness. Ultimately, using what’s in season will yield the best results. Makes 1½ cups syrup
Combine orange zests, orange juices, lime zest, and honey (or sugar) in a saucepan over medium heat. Bring to a boil, stirring until the sugar dissolves. Stir in the citric acid. Remove pan from heat and let cool to room temperature. Strain syrup through a fine-mesh sieve into a bowl. Pour the orange syrup into airtight containers and store in the refrigerator for up to 2 weeks.
To make a glass of orange soda: Pour ¹⁄³ cup of orange syrup into a tall glass, add seltzer, and stir gently. Add ice, garnish with an orange slice, and serve.