Place the green beans and the onions in a large skillet over medium high heat.  Toss the green beans and the onions until the beans start to soften and the onions caramelize.  Splash some of the balsamic glaze in the pan after a few minutes when the beans and onions start to brown a bit.

While the beans are cooking, place the Dijon mustard and the vinegar in a small bowl and whisk together. 

Pour the mustard sauce on top of the beans and finish cooking.  The beans should be slightly crisp, not mushy.  Garnish with toasted almonds and salt & pepper