diff --git a/examples/bluetooth/nimble/bleprph/CMakeLists.txt b/examples/bluetooth/nimble/bleprph/CMakeLists.txt
index 4ed234067a..ef14737a80 100644
--- a/examples/bluetooth/nimble/bleprph/CMakeLists.txt
+++ b/examples/bluetooth/nimble/bleprph/CMakeLists.txt
@@ -5,7 +5,8 @@ cmake_minimum_required(VERSION 3.22)
 # Include the Bluetooth-optimized mbedTLS preset configuration
 # This provides optimized settings for Bluetooth applications
 # You can customize these settings using 'idf.py menuconfig' or additional config files
-list(APPEND sdkconfig_defaults $ENV{IDF_PATH}/components/mbedtls/config/mbedtls_preset_bt.conf)
+cmake_path(CONVERT "$ENV{IDF_PATH}" TO_CMAKE_PATH_LIST ESP_IDF_PATH)
+list(APPEND sdkconfig_defaults "${ESP_IDF_PATH}/components/mbedtls/config/mbedtls_preset_bt.conf")
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 # "Trim" the build. Include the minimal set of components, main, and anything it depends on.
 idf_build_set_property(MINIMAL_BUILD ON)