Combine the soy sauce, vinegar, maple syrup, garlic, ginger, sesame oil (or tahini), and pepper flakes in a small bowl. In a separate bowl or mug, dissolve the starch in water. Don't add the starch slurry to the sauce just yet. Set aside.
Preheat a large, oven-safe skillet over medium heat. Position the top oven rack about 6 inches from heat source and set broiler to 500 degrees.
Wet your fingers and flick a bit of water into the pan. If the water beads and dances across the surface, the pan is ready and the tofu won't stick. Place each piece of tofu in the pan, careful not to move them once placed. They may pop and sputter but don't worry! There's no oil to burn you. Turn off the eye and transfer the pan to the oven. Broil until the tops are golden brown, 7 to 10 minutes.
Carefully remove pan from oven and flip the tofu. Return pan to oven and broil for another 6 to 8 minutes.
Transfer the pan to the stove top and turn the eye on medium-low. REMEMBER, the handle is HOT. For safety, slide an oven mitt onto the handle as a reminder.
Mix the starch slurry into the sauce and pour over the tofu. Add the broccoli to the pan. Cook for about 5 minutes, stirring occasionally to coat the tofu and broccoli with sauce. Once the sauce has thickened and the broccoli can be pierced with a fork, garnish with green onion and sesame seeds and serve.
This high-heat broiling method is a great way to achieve a meaty, chewy exterior for your tofu without the use of oil. Use it in different recipes and with a variety of sauces!*Nutrition information calculated using toasted sesame oil and includes sesame seed garnish. Based on four servings.Storage: store leftovers in the refrigerator for up to 4 days.