Mix the flanks steak slices with the tapioca starch, and combine until well coated.
2 lbs. flank steak, ¼ cup tapioca starch
Melt the coconut oil in a skillet over medium-high heat.
¼ tbsp. coconut oil
Add the beef in batches, cook until browned on all sides, then set aside.
Add the garlic, bell pepper, carrots, and mushrooms to the skillet, and sautée for 2 to 3 minutes.
1 bell pepper, 2 carrots, 4 garlic cloves, 8 oz. mushrooms
Pour in the beef stock while scraping the bottom of the pan.
½ cup beef stock
Add the coconut aminos and season to taste; cook for 2 to 3 minutes.
½ cup coconut aminos, Sea salt and freshly ground black pepper
Bring the beef back to the pan, add the green onions, and cook for another 2 to 3 minutes.
3 green onions
Sprinkle with red pepper flakes and serve.
¼ tsp. red pepper flakes