Preheat your oven to 400 F. Line a baking tray with parchment.
In a large bowl, whisk together the cornmeal, milk and oil. Toss your florets in to coat. Transfer them to the baking tray and spread out. Roast for 17-20 minutes or until crusty.
Sauce:
Meanwhile, make your sauce in a medium pan, combine the broth, lemon juice, honey, vinegar, garlic and salt to taste. Heat for 2-3 minutes. Once warmed through, add in the cornstarch and keep whisking until the sauce thickens. Remove promptly and toss with your roasted cauliflower. Top with the lemon zest and serve.