That worked for me:
(just past this in a file called whatever.bat and run it)
@echo off
for /f "eol=: delims=" %%F IN ('dir /b /s "C:\Users\MyPC\Desktop\myDir\*.txt"') do (
(
echo %%~nF
echo ___________________________
type "%%F"
)>"%%F.new"
move /y "%%F.new" "%%F"
)
pause