Preheat your oven to 425°F (220°C). Line a large baking sheet with parchment paper or aluminum foil for easy cleanup.

Wash and chop all the vegetables into uniform, bite-sized pieces. In a large mixing bowl, combine broccoli, cauliflower, bell peppers, zucchini, and red onion.

Drizzle with olive oil, then add minced garlic, oregano, thyme, rosemary, salt, and pepper. Toss everything together until evenly coated.

Spread the vegetables in a single layer on the prepared baking sheet. Avoid overcrowding to allow them to roast instead of steam.

Roast in the preheated oven for 30-35 minutes, flipping halfway through, until the vegetables are fork-tender with crispy edges.

After roasting, give the veggies a squeeze of lemon juice and sprinkle with chopped parsley or basil before serving.