Behat with PhpStorm does not show stack trace for exceptions

Yup, been there, done that… Guys at JetBrains know about this, but no fix version has been set yet. Vote on the issue, this will speed things up.

So in the 5+ years since this question was asked, PHPStorm has implemented what it has needed, but you still need to know the totally cryptic Behat command-line option, and where to put it. Anyway, this is where desperate Google-searching got me, so let me put the answer here.

Under Run menu, Edit configurations..., select the Behat template, and in the Test Runner options field, put -vv.

Then your Behat fails will the full error message and a stack trace.