Prepare the Rack of Lamb: Preheat the oven to 375°F (190°C). Season the lamb generously with salt and pepper. Heat olive oil in a skillet over medium-high heat and sear the lamb on all sides until golden brown. In a bowl, combine the parsley, rosemary, thyme, garlic, and breadcrumbs. Press the herb mixture onto the lamb, coating it evenly. Roast in the oven for 20-25 minutes, until the internal temperature reaches 125°F for medium-rare. Let the lamb rest before slicing.
Make the Mint Chimichurri: In a food processor, combine the mint, parsley, lemon juice, red pepper flakes (if using), and olive oil. Pulse until smooth. Season with salt and pepper to taste.
Roast the Vegetables: Preheat the oven to 425°F (220°C). Toss the chopped vegetables with olive oil, rosemary, salt, and pepper. Spread in a single layer on a baking sheet and roast for 25-30 minutes, stirring halfway through, until golden and crispy.
Plate and Serve: Slice the rack of lamb into individual chops and arrange them on the plate. Drizzle with mint chimichurri and serve with roasted root vegetables. Garnish with fresh herbs.