1. Preheat oven to 200°C
2. Slice vegetables into chunks roughly 1.5 inches wide.
3. Place cut vegetables and garlic cloves into a large mixing bowl. Add 3 tbsp olive oil, fresh thyme leaves, ground cumin, kosher salt, and black pepper. Stir until all vegetables are evenly coated with oil, spice and herbs.
4. Brush large rimmed baking sheet with remaining 1 tbsp olive oil. Spread the vegetables out evenly on the baking sheet. Place the rosemary sprigs on top of the vegetables, evenly spaced across the sheet.
5. Roast the vegetables in the oven for 15 minutes. Stir the vegetables to ensure even cooking. Return baking sheet to oven and continue to roast until the largest chunks are tender and the edges are starting to turn golden/dark, another 15-25 minutes.
6. Remove the roasted rosemary sprigs and stir the vegetables. Season with additional salt and pepper to taste, if desired.