Preheat your oven to 425°F (220°C). Prepare a large baking sheet by lining it with parchment paper or lightly greasing it with olive oil.

Rinse and chop your carrots, zucchini, cauliflower, and red onion into bite-sized pieces.

In a large mixing bowl, toss your chopped vegetables with olive oil, cumin, salt, and black pepper until well-coated.

Spread the seasoned vegetable mixture evenly on the prepared baking sheet and roast for 25–30 minutes, stirring halfway through.

Check the vegetables for doneness; they should be fork-tender and slightly crisp on the edges.

Remove from oven, drizzle with fresh lemon juice, and sprinkle with parsley before serving.