diff --git a/src/pydata_sphinx_theme/toctree.py b/src/pydata_sphinx_theme/toctree.py
index dcc76228f0..38ee763b2e 100644
--- a/src/pydata_sphinx_theme/toctree.py
+++ b/src/pydata_sphinx_theme/toctree.py
@@ -113,7 +113,7 @@ def unique_html_id(base_id: str):
         return next(get_or_create_id_generator(base_id))
 
     @cache
-    def _generate_nav_info() -> List[LinkInfo]:
+    def _generate_nav_info(self) -> List[LinkInfo]:
         """Generate informations necessary to generate nav.
 
         Instead of messing with html later, having this as a util function