Longtime fans of the eye-watering hot sauce from Geno's Steaks can now take some to go. The company is selling bottles of its signature condiment at the South Philly counter, as well as at the retail shop across the street.

Launched in late June, the bottled sauce is made from vinegar, red bell peppers, salt, and bird's-eye peppers, a piping-hot variety often found in Southeast Asia. The sauce is spicy and sharp, with a mouth-clenching tang from the vinegar.

The idea behind the sauce, created in 1966 by Geno's founder, Joey Vento, was always to add heat without overpowering the classic taste of the cheesesteak. The flavors of the sauce are simple enough to add a solid kick to eggs or other traditional hot-sauce vehicles.

Geno's Hot Sauce, $7 at Geno's Steaks, 1219 S. Ninth St., or Geno's Gear, 1225 E. Passyunk Ave.; genosteaks.com.