Preheat oven to 400 degrees Fahrenheit.

Place potatoes in a pot of water.

Bring to a boil and boil for 2 minutes.

Drain the potatoes.

Quickly rinse with cold water.

Set the potatoes aside.

Heat olive oil in an ovenproof pan over medium-high heat.

Add onion slices to the pan.

Sauté the onions until slightly browned.

Add chopped garlic to the pan.

Sauté the garlic and onions for about 10 minutes more, until onions are caramelizing.

Transfer the onions and garlic to a bowl.

Melt butter in the bottom of the pan, scraping up any browned bits.

Add the potatoes and onions back to the pan.

Stir gently to combine with the butter.

Season to taste with salt and pepper.

Bake in the preheated 400 degree F oven for about 20 minutes or until potatoes are tender and lightly browned on top.