Rose water, lemon juice & chilled water — Persia's royal cooler
Persian sharbat is the ancestor of every sweetened drink in the world — the word 'sherbet', 'sorbet', and even 'syrup' all derive from the Arabic-Persian root sharba. At its simplest, Sharbat-e-Golab is three ingredients: rose water, sugar, water. The Persians understood that the best drinks don't need many ingredients.
Persian rose water is noticeably more fragrant than other brands — look for Golab brands from an Iranian grocery. Start with less rose water — it's easy to add more, impossible to undo. For a more complex version, add ½ tsp basil seeds (tukhm-e-sharbati) which bloom into a tapioca-like gel.