Set oven to 420F.
Wash potatoes then pierce them several times with a fork. Place them on a baking sheet, then bake in the oven for about 50 minutes until you can easily pierce them with a knife or fork. Allow them to cool on a baking rack until they can be handled.
Set oven to broil.
Set a nonstick skillet on medium high heat and spray it with avocado oil. Toss in onions, garlic and bell pepper and cook for about 3 to 5 minutes, until the onions are brown and translucent. Do NOT burn the garlic.
Add the flank steak and cook for an additional 6 to 8 minutes, until desired readiness.
Slice each potato in half, lengthwise. Scoop out the flesh but leave about a 1/4-inch in the potato. Set aside the scooped out potato for another recipe but don’t toss it away.
Spray the halves with avocado oil, then sprinkle on the skin seasonings.
Broil the halves for roughly 6 minutes, flipping halfway through. Begin with skin side up (open face down), then flip up for the remaining time, until the edges are crispy.
Remove the halves from the oven, then add mozzarella cheese, steak mix, then Monterrey jack cheese.
Broil for an additional 2 to 3 minutes until the cheese has melted.
Remove from the oven, then garnish and enjoy.