ba ba ba ba penuts - It's the sound of your brain turning to mush when someone sa

It's the sound of your brain turning to mush when someone says something stupid and you just repeat it back at them

'I'm going to win the Olympics!' 'Ba ba ba ba penuts.'

'I just ate ten burgers!' 'Ba ba ba ba penuts.'

'I'm the smartest person alive!' 'Ba ba ba ba penuts.'