Peel and cut carrots into 1/2-inch diagonal slices (about 3 cups). Trim and halve zucchini lengthwise then cut into 1/2-inch half-moons (about 2 cups). Seed and cut red and yellow bell peppers into 1-inch pieces (1 cup each). Peel red onion and cut into 1-inch wedges (1 cup). Cut broccoli into bite-sized florets (2 cups). Leave cherry tomatoes whole or halve larger ones (1 cup).

Seasoning & Toss

In a large mixing bowl, whisk together extra-virgin olive oil (3 tbs), minced garlic (2 tsp), dried thyme (1 tsp), crushed dried rosemary (1 tsp), smoked paprika (1 tsp), kosher salt (1 tsp), freshly ground black pepper (1 tsp), and red pepper flakes if using (0.25 tsp).

Add all prepared vegetables to the bowl and toss thoroughly so every piece is lightly coated with the oil and seasoning mixture. Spread the vegetables in a single layer on the prepared baking sheet, arranging similar-density vegetables (carrots and broccoli) so they have space and are not overcrowded. Place cherry tomatoes on top or to one side to avoid overcooking.

Roasting

Roast in the preheated oven for 18 minutes. After 18 minutes, remove the sheet and use a spatula to flip denser vegetables (carrots, broccoli) and move tender vegetables (zucchini, tomatoes) if they are browning too quickly. Return to oven and roast an additional 7–10 minutes, until carrots are fork-tender and edges of peppers and onions are caramelized and slightly charred.

If you prefer more browning, switch oven to broil for the final 1–2 minutes, watching carefully to avoid burning.

Finish & Serve

Remove the tray from the oven and transfer vegetables to a serving bowl. Drizzle with fresh lemon juice (1 tbs) and sprinkle chopped fresh parsley (2 tbs). If using, grate Parmesan (2 tbs) over the warm vegetables. Taste and adjust salt and pepper as needed.

Serve warm as a side dish or cool to room temperature and use in salads, grain bowls, or sandwiches. Leftovers refrigerate in an airtight container for up to 4 days.