Slice the flank steak into thin strips across the grain to ensure tenderness.
In a medium bowl, toss the steak strips with chili powder, cumin, sea salt, black pepper, and the juice from the lime.
Heat 0.5 tsp of olive oil in a large skillet over medium-high heat and sauté the sliced peppers and onions until they are tender-crisp and slightly charred.
Remove the vegetables from the skillet and set them aside on a plate.
Add the remaining 0.5 tsp of olive oil to the same skillet and sear the steak strips for 2-3 minutes until they are browned and sizzling.
Wipe the skillet clean and place the tortilla in the pan over medium heat.
Sprinkle half of the Monterey Jack cheese onto one side of the tortilla, then layer on the cooked steak and sautéed vegetables.
Top with the remaining cheese and fold the tortilla in half.
Cook for 2-3 minutes per side until the tortilla is golden and crispy and the cheese has fully melted.
Remove from the heat, let it rest for one minute, then slice into wedges and serve.