Preheat the oven to 425°F and line a baking sheet with parchment paper. Trim and slice the Brussels sprouts in half. Place them in a bowl and toss with a drizzle of extra-virgin olive oil, sea salt, and freshly ground black pepper until evenly coated.

Arrange the seasoned Brussels sprouts in a single layer on the prepared baking sheet. Roast for 20 to 30 minutes, or until the sprouts are tender and their edges are golden brown. I like to check for deep, caramelized color for the best flavor.

Transfer the hot, roasted Brussels sprouts to a serving bowl. Toss immediately with fresh lemon juice, lemon zest, grated Parmesan, and fresh thyme leaves. Garnish with fresh parsley leaves and a pinch of red pepper flakes. For even more brightness, I squeeze a little extra lemon juice just before serving.