Caramelized onions make a great side dish for any meat.  I always prepare them with a steak and I’ve even made them for a side of baked salmon.  In most cases, regular onions will work but if you want the best onion for the job, I’d pick a Maui onion

Ingredients
4 teaspoons butter
1 large Maui onion

Method
Cut the onion into quarters (half and then half again).  Slice the onion–about 5 centimeter slices.  Add the butter to a saute pan over medium low heat.  Do not let the butter burn.  In fact, once half the butter is melted, add the onions.  Periodically stir the onions every 5 minutes.  This is something you can do on one of the backburners that you’re not using.  You’ll see the onion start to darken.  At this point the sugars are coming out of the onion and are starting to caramelize.  After 25 to 30 minutes you’ll have a sweet side of caramelized onions.

Notes
If you can’t find Maui onions, use another onion and you might have to add a sprinkle of brown sugar once the onions start to brown.  You can substitute the butter with olive oil.  If you are using unsalted butter, add a dash or two.  The salt will bring out the natural flavors.

If you recently pan seared a meat, use the same pan to make the caramelized onions.  This will add more flavor.  You might want to deglaze the pan with a little vegetable stock or wine before adding the butter.