Ribeye Steak with Caramelized Onions and Mashed Potatoes

Ribeye Steak with Caramelized Onions and Mashed Potatoes
Ingredients

• 2 ribeye steaks (about 1-inch thick)
  Salt and black pepper (to taste)
  1 tbsp olive oil
  2 tbsp unsalted butter (divided)
  2 medium onions (thinly sliced)
  1/4 cup beef broth (optional, for deglazing)
  Mashed Potatoes:
  4 large russet potatoes (peeled and cubed)
  1/2 cup whole milk (warmed)
  1/4 cup unsalted butter
  Salt and pepper to taste