Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Peel the carrots and parsnips, then slice them into half-inch thick rounds to ensure even roasting.
In a medium bowl, toss the sliced vegetables with the extra virgin olive oil, sea salt, black pepper, and dried thyme until well coated.
Spread the seasoned root vegetables in a single layer on the prepared baking sheet and roast for 15 minutes.
While the vegetables roast, whisk together the honey and Dijon mustard in a small bowl until the glaze is smooth.
Remove the tray from the oven, push the vegetables to one side, and place the ham steak on the other side of the sheet.
Brush the honey-mustard glaze generously over both sides of the ham steak using a pastry brush or spoon.
Return the baking sheet to the oven and roast for an additional 10 to 12 minutes until the ham is heated through and the vegetables are tender and golden.
Serve the glazed ham immediately alongside the roasted vegetables for a balanced, clean-eating dinner.