Add the beef, 2 tbsp cornstarch and 3 tablespoons of the mirin together in a ziploc bag and squeeze the bag a few times to combine.
Let marinate in the refrigerator for 30 min
Partially steam broccoli florets for 2 min in microwave steamer (or bowl covered with plastic wrap) and 2 tbsp water until crisp-tender
In a separate bowl, combine ginger, hoisin, fish sauce, water, 2 tbsp mirin, stevia, soy sauce and corn starch and whisk together. Be sure cornstarch dissolves completely
Heat a non-stick skillet on high - the hotter the better
When pan is hot, add sesame oil to the pan - it should ripple and pop a little
Add shaved steak and minced garlic
Sear on high for 1-2 minutes - stirring so it doesn't stick
Add in broccoli and toss gently
Stir sauce in bowl to be sure corn starch hasn't settled. Then add to the pan with beef & broccoli
Turn off the heat and quickly toss to combine - the sauce should thicken quickly and coat all of the beef & broccoli
Serve with rice or cauliflower rice and top with sesame seeds for garnish