Slow-Roasted Root Vegetables with Herb-Infused Olive Oil

By Lauren Mitchell, Test Kitchen Director · Reviewed by AislePrompt Editorial · Published 2026-04-20 · Updated 2026-04-20

Root vegetables roasted at a low temperature for hours to develop deep sweetness without browning, finished with a fragrant herb oil. This mediterranean-inspired sheet pan ready in about 60 minutes pairs olive oil, minced garlic, finely chopped fresh rosemary for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 220 calories and feeds 4, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Ingredients

• 2 medium, peeled and cut into 1-inch pieces carrots
• 2 medium, peeled and cut into 1-inch pieces parsnips
• 1 large, peeled and cut into 1-inch pieces sweet potato
• 1 medium, cut into 1-inch wedges red onion
• 3 tbsp olive oil
• 2 cloves, minced garlic
• 1 tsp, finely chopped fresh rosemary
• 1 tsp, leaves only fresh thyme
• 1/2 tsp salt
• 1/4 tsp black pepper

Instructions

1. Step 1: Preheat oven to 275°F and line a baking sheet with parchment paper. In a large bowl, combine carrots, parsnips, sweet potato, and red onion. Drizzle with 3 tbsp olive oil, then add minced garlic, 1 tsp chopped rosemary, 1 tsp thyme, 1/2 tsp salt, and 1/4 tsp black pepper. Toss until vegetables are evenly coated.
2. Step 2: Spread vegetables in a single layer on the prepared baking sheet. Roast for 45 minutes, stirring once halfway through, until tender and lightly caramelized at the edges.
3. Step 3: Remove from oven and let cool for 5 minutes. Transfer to a serving dish and sprinkle with an additional 1/2 tsp fresh rosemary and 1/2 tsp thyme for garnish before serving.