diff --git a/HACKING.rst b/HACKING.rst
index f97f97a..c0a857c 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -246,7 +246,7 @@
 to the config variables in tempest/config.py then the sample config file must be
 regenerated. This can be done running::
 
-  tox -egenconfig
+  tox -e genconfig
 
 Unit Tests
 ----------