How to Make It
Mix the water, sugar, and fruit together in a medium saucepan. Bring the mixture to a boil, stirring to ensure the sugar dissolves.
After the syrup boils, reduce the heat to low and simmer for 5-10 minutes, or until slightly thickened.
Pour the syrup over a fine mesh sieve balanced over a bowl and let the syrup strain on its own. You’re going to want to press down on the fruit to drain out every last drop of moisture (and I know, mushing things is just plain fun) but resist the urge. Larger bits of fruit pulp will make the syrup cloudy, which isn’t what we’re going for here. Instead, save that mushy fruit for spooning over yogurt or blending into a smoothie.
After the strained simple syrup has cooled a bit, fill a glass halfway with ice. Spoon in syrup until it just barely covers the ice. Fill the glass with very fizzy seltzer and swirl just a bit with a spoon. If you’d like to turn the Italian soda into a French soda (also known as an Italian cream soda), pour a bit less seltzer into the glass and top the drink with a splash of heavy cream.