**I’d start with a small jar of Curio Spice’s Lebanese sumac.** It lists only dried, ground sumac and describes the flavor as tart, fruity and citrusy—a promising match for what you remember.

Two specific online options, especially if you’re in the U.S.:

- **[Curio Spice Lebanese Sumac](https://curiospice.com/products/sumac-lebanese):** Finely ground, sourced from Lebanon, with no added salt listed.
- **[Burlap & Barrel Cured Sumac](https://www.burlapandbarrel.com/products/cured-sumac):** Turkish sumac with sour-cherry and vinegar-like tasting notes. It contains 6% salt, so account for that when seasoning.

Those are the sellers’ descriptions; I can’t guarantee either will match your friend’s batch. Asking your friend for their supplier would give you the best lead.

For an in-person purchase, try a Persian grocer and ask whether you can taste a pinch before buying. Given your two disappointing purchases, that would be especially useful. Buy a small quantity first.

What country or city are you shopping in?