Rinse sprouts under cold water. Peel off yellow or damaged outer leaves and trim the stem ends. Halve each sprout lengthwise through the core — the flat cut side browns and caramelizes. Quarter any very large sprouts so everything cooks evenly. Pat thoroughly dry with a kitchen towel or paper towels; moisture steams instead of roasts. Toss in a Mixing Bowl with enough olive oil to lightly coat, then season generously with kosher salt and black pepper.

Preheat Oven to 425°F, rack in upper third. Line a Baking Sheet with Parchment Paper or Aluminum Foil. For extra caramelization, preheat the empty pan in the oven. Spread seasoned sprouts cut side down in a single layer — don't crowd the pan; use two pans if needed. Roast at 425°F for 20–30 minutes. Check at 15 minutes. Done when cut sides are deep golden brown and outer leaves are crispy.

Preheat your Air Fryer to 375°F for 3 minutes. Arrange the 1 ½ lb Brussels sprouts trimmed and halved lengthwise in a single layer, cut-side down, in the Air Fryer basket. Work in batches if needed — overcrowding prevents crisping. Air fry at 375°F for 12–15 minutes, shaking the basket halfway through, until the cut sides are deeply golden and the outer leaves are crispy.

Transfer the hot 1 ½ lb Brussels sprouts trimmed and halved lengthwise to a serving Mixing Bowl. Immediately drizzle with 1 ½ tbsp balsamic glaze drizzled after cooking and a squeeze of fresh 1 tsp lemon juice freshly squeezed, then toss gently. Top with freshly grated 3 tbsp Parmesan cheese freshly grated and serve right away.