diff --git a/docs/source/llm/getting-started.md b/docs/source/llm/getting-started.md
index 7d54f4d2dde..06705c2e4d5 100644
--- a/docs/source/llm/getting-started.md
+++ b/docs/source/llm/getting-started.md
@@ -362,6 +362,7 @@ set(CMAKE_CXX_STANDARD_REQUIRED True)
 option(EXECUTORCH_ENABLE_LOGGING "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_DATA_LOADER "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_MODULE "" ON)
+option(EXECUTORCH_BUILD_EXTENSION_FLAT_TENSOR "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_TENSOR "" ON)
 option(EXECUTORCH_BUILD_KERNELS_OPTIMIZED "" ON)
 
@@ -517,6 +518,7 @@ set(CMAKE_CXX_STANDARD_REQUIRED True)
 option(EXECUTORCH_ENABLE_LOGGING "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_DATA_LOADER "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_MODULE "" ON)
+option(EXECUTORCH_BUILD_EXTENSION_FLAT_TENSOR "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_TENSOR "" ON)
 option(EXECUTORCH_BUILD_KERNELS_OPTIMIZED "" ON)
 option(EXECUTORCH_BUILD_XNNPACK "" ON) # Build with Xnnpack backend
diff --git a/examples/llm_manual/CMakeLists.txt b/examples/llm_manual/CMakeLists.txt
index 1283eb548ea..056e352cb0f 100644
--- a/examples/llm_manual/CMakeLists.txt
+++ b/examples/llm_manual/CMakeLists.txt
@@ -13,6 +13,7 @@ set(CMAKE_CXX_STANDARD_REQUIRED True)
 # Set options for executorch build.
 option(EXECUTORCH_BUILD_EXTENSION_DATA_LOADER "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_MODULE "" ON)
+option(EXECUTORCH_BUILD_EXTENSION_FLAT_TENSOR "" ON)
 option(EXECUTORCH_BUILD_EXTENSION_TENSOR "" ON)
 option(EXECUTORCH_BUILD_KERNELS_OPTIMIZED "" ON)
 option(EXECUTORCH_BUILD_XNNPACK "" ON) # Build with Xnnpack backend