Preheat the broiler. In a medium skillet, heat 2 tablespoons of olive oil until shimmering. Add the garlic, bay leaf and thyme sprigs and cook over moderate heat until fragrant, 2 minutes. Add the artichokes and lemon zest and cook, stirring, until lightly browned, 5 minutes. Scrape the thyme leaves into the skillet; discard the sprigs and bay leaf.