Sgt. Frog

The Episode We Wanted to Call Tiny Toons or Animaniacs, But Those Were Already Taken (1x33)

:

Witnessing the merchandising power of the 'Admiral Geroro' anime, Keroro hatches a new scheme to conquer Earth throuugh the creation of his own anime - but the actual process, from storyboarding to artwork to animation, prove far too troublesome and frustrating for the Keroro platoon to handle. They pay a visit to an actual animation studio, picking up the tricks of the trade, and after returning to work, the final product is ready for viewing - but Keroro decides that more work is needed, and returns to the research & development stage (the fact that said final product turned out to be quite horrible isn't even brought up).