Broccoli with Balsamic Caramelized Onions

I am involved in the Sidedish Showdown at Cinnamon Spice and Everything Nice.  We have been cooking and writing about side dishes that we are creating at home.  You ought to go and check out the other submissions.  There is some great food listed!

We eat a lot of broccoli in my house.  It is one of the only green foods that my husband and son will eat (and he won't eat that much).  I know we all get tired of the boring steamed broccoli so I wanted to change things up a little.  This is what I came up with.

2 cups red onions, sliced thinly
2 tbsp of olive oil
1 tbsp balsamic vinegar
salt and pepper to taste
4 cups steamed broccoli
1 tbsp of butter
asiago cheese
Chopped parsley and basil (optional)

Add oil to a large nonstick pan over medium high heat.  Saute onions until caramelized (about 20 minutes).  Add vinegar and cook for 5 minutes.  Salt and pepper to taste.  Add steamed broccoli and butter and cook together for 3 minutes.  Remove from heat and top with cheese, parsley and basil.