Asian-inspired Flank Steak - Today's Parent

Ingredients

• 1/2 medium onion, sliced
• 1 to 2 garlic cloves, smashed
• 1 tbsp tamari, or soy sauce
• 1 tsp sesame oil
• lime juice, from 1/2 lime
• 1 tbsp maple syrup, or brown sugar
• pinch hot-pepper flakes, (optional)
• 1 800-g to 1.5-kg beef flank steak
• salt, to taste
• black pepper, to taste