1-First Step: Prepare Your Equipment Preheat your oven to 425°F. This high temperature is crucial for achieving caramelization without overcooking the interior. Line a baking sheet with parchment paper for easy cleanup and to prevent sticking. The parchment also helps the sprouts roast evenly without burning on the bottom.

2-Second Step: Clean and Prep the Brussels Sprouts Rinse your Brussels sprouts under cold water to remove any dirt or debris. Pat them dry thoroughly with a clean kitchen towel excess moisture is the enemy of crispiness. Trim off the tough bottom stems and remove any dry, discolored, or woody outer leaves. For uniform cooking, slice Brussels sprouts larger than 1 inch in half lengthwise. Keep smaller sprouts whole to prevent them from overcooking.

3-Third Step: Season and Coat Place the prepared Brussels sprouts in a large bowl. Drizzle generously with olive oil about 2 to 3 tablespoons per pound works well. Sprinkle with sea salt and freshly ground black pepper to taste. Toss everything together with your hands or a spoon until every sprout is evenly coated. The oil helps conduct heat for better browning and keeps the exterior crisp rather than leathery.

4-Fourth Step: Arrange on Baking Sheet Transfer the seasoned Brussels sprouts to your prepared baking sheet. Arrange them cut side down in a single layer. This positioning allows the flat side to have direct contact with the hot pan, creating that beautiful golden-brown caramelization. Don’t overcrowd the pan if the sprouts are too close together, they’ll steam instead of roast, resulting in soggy exteriors. Save those loose leaves that fall off during prep and scatter them on the baking sheet too; they become delightfully crispy chips.

5-Fifth Step: Roast to Perfection Place the baking sheet in your preheated oven and roast for 20 to 30 minutes. Check at the 20-minute mark shake the pan or use tongs to flip the sprouts for even browning. They’re done when fork-tender in the center with golden-brown, slightly charred edges. Smaller sprouts or halves may be ready closer to 20 minutes, while larger ones might need the full 30 minutes.

6-Sixth Step: Add Final Seasonings If using the optional lemon Parmesan seasoning, remove the sprouts from the oven and immediately transfer them to a bowl. While they’re still hot, toss with the lemon juice, lemon zest, Parmesan cheese, and fresh thyme leaves. The heat helps the cheese melt slightly and the herbs release their aromatic oils. Taste and adjust seasoning as needed. Garnish with fresh parsley and a pinch of red pepper flakes before serving.