Pat the flank steak dry and season both sides with sea salt, black pepper, garlic powder, and ground cumin.
Heat a cast-iron skillet over medium-high heat with the avocado oil until shimmering.
Sear the steak for 3-4 minutes per side until a golden-brown crust forms, then remove from the pan and let it rest for 5 minutes before thinly slicing against the grain.
In a small bowl, whisk together the large egg and egg whites until well combined.
Reduce the skillet heat to medium-low and pour in the egg mixture, stirring gently until the eggs are fluffy and just set.
Warm the grain-free tortilla in a separate dry pan for 30 seconds per side until pliable.
Assemble the burrito by layering the sliced steak, scrambled eggs, fresh avocado slices, and salsa in the center of the tortilla.
Garnish with fresh cilantro, roll tightly, and serve immediately while warm.