Preheat oven to 425. Coat potato in oil and season with salt and pepper. Using a fork, pierce the potato. Bake in the oven for about an hour or until potato is softened enough to stick through with a fork. (Alternatively, you could microwave for about 7 min or so) Meanwhile, thinly slice the onions and add to a skillet with 2 tbsp butter. Season with salt and pepper. Cook, stirring often for about 20 minutes. If the pan is dry, add a little water or broth and let the onions cook down in the liquid.
When potatoes are soft and done, scoop out the middle of the potato, being careful to not break through the bottom of the skin. Crank oven to broil.
Add the potato middles to a bowl with gruyere cheese, caramelized onions, cream cheese, and 1 tbsp butter to a bowl and mix until creamy and combined. Scoop back into the potato and top with more gruyere cheese.
Broil for 3-5 minutes until browned and bubbly. Top with chopped chives and that’s it! Enjoy!