Place this clip right after the fumbled line in your edit, then follow it with awkward crickets to let the reaction settle before you cut back to normal dialogue or add a light laugh track underneath the next scene.
Über diesen Sound
This is a short voice clip, just under five seconds, of Stéphano drawing out the French phrase 'tu bégayes' into a long, teasing 'bégayyyyyes'. The delivery feels playful and mocking, turning a simple stumble into an awkward, funny call-out that listeners instantly read as friendly ribbing rather than a real insult during conversation.