Instructions:
- Prepare the Marinade: In the large mixing bowl, whisk together the olive oil, minced garlic, chopped rosemary, thyme, lemon zest, lemon juice, salt, and pepper until emulsified.
- Chop Vegetables: Cut all primary vegetables (zucchini, peppers, onion) into uniformly sized pieces suitable for grilling. Keep the asparagus spears whole.
- Marinate: Add all prepared vegetables to the bowl with the marinade. Toss thoroughly to ensure every piece is coated. Allow to sit at room temperature for 15–20 minutes while the grill heats up.
- Preheat the Grill: Preheat your grill to a medium-high heat (around 400°F/200°C). Ensure the grates are clean and lightly oiled.
- Grill in Batches: Place the larger, sturdy vegetables (peppers, onions) directly on the grates first. Grill for 3–4 minutes per side until softened and developing good char marks.
- Add Softer Vegetables: Add the zucchini and mushrooms. Cook, turning frequently, for another 5–8 minutes total, until tender-crisp.
- Finish Asparagus: Grill the asparagus spears, turning often, until bright green and lightly blistered, about 3–5 minutes.
- Taste and Serve: Remove all vegetables from the grill. Taste one piece and adjust seasoning with a final pinch of salt or squeeze of lemon juice if needed. Serve immediately while hot.