Preparation: Wash all vegetables thoroughly. Slice zucchini into half-inch rounds. Deseed the bell peppers and cut them into large, grill-friendly pieces. Separate broccoli into small florets.
Marination: In a mixing bowl, combine the soy sauce, olive oil, minced garlic, red chili flakes, salt, and pepper. Whisk well until everything is integrated. Toss in the vegetables, ensuring they’re well-coated with the marinade. Let them sit for at least 10 minutes.
Grill Setup: Preheat your grill on medium heat. Ensure the grates are clean and slightly oiled to prevent sticking.
Grilling Time: Place the vegetables on the grill. Cook the bell peppers for about 5-6 minutes on each side or until they have those beautiful char marks. Zucchini might take around 4 minutes on each side. Broccoli florets usually grill faster, roughly 3 minutes per side. Remember to brush the vegetables with any leftover marinade occasionally.
Serve Hot: Once grilled to perfection, transfer the Spicy Grilled Vegetables with Soy Sauce to a plate.