Bring your mise en place: pat the 180 g chicken breast dry with paper towels (drying promotes an even, golden sear), season both sides generously with sea salt and freshly cracked black pepper. Mince the garlic, chop the oregano and parsley, zest the lemon, and slice the red onion very thin. Halve the Brussels sprouts if not already halved.

Preheat the oven to 425°F (220°C). A very hot oven lets the cut faces of the Brussels sprouts caramelize quickly, producing sweet, nutty flavors rather than steaming them.

Toss the halved Brussels sprouts with 1 tablespoon extra-virgin olive oil, a pinch of salt and a few grinds of black pepper on a rimmed baking sheet, cut-side down. Roast for 14–18 minutes until the edges are deeply browned and the centers are tender when pierced with a knife. Placing them cut-side down maximizes contact with the hot pan and encourages Maillard browning for better flavor.

While the sprouts roast, make the lemon-oregano sauce for the chicken: in a small bowl combine 1 tablespoon olive oil (for pan), minced garlic, 1 tablespoon chopped fresh oregano (or 1 tsp dried), 1 tablespoon lemon juice and 1/4 tsp lemon zest, plus a pinch of salt and pepper. This bright, oil-based marinade doubles as a finishing sauce and is kept simple to let the lemon and oregano shine.

If you have a meat mallet, place the chicken between plastic wrap and gently pound to an even thickness (about 1/2–3/4 inch). Why: an even thickness ensures the chicken cooks through at the same rate and prevents the thinner end from drying out while the thick end finishes.

Heat a heavy skillet (cast iron recommended) over medium-high heat until shimmering. Add the 1 tbsp olive oil reserved for the chicken and swirl to coat. A properly heated pan is essential to get an immediate sizzle when the chicken hits the surface — that sizzle creates a golden crust and caramelized flavor.

Place the chicken in the hot pan and sear without moving for 3–4 minutes, until a deep golden-brown crust forms. Flip and reduce heat to medium; pour half of the lemon-oregano mixture over the chicken and continue cooking another 3–5 minutes, basting with the pan juices, until the internal temperature reaches 160–165°F (71–74°C). Searing first builds flavor through the Maillard reaction; finishing at a slightly lower heat ensures it cooks through gently without burning the garlic in the sauce.

Remove the chicken from the pan and let it rest on a warm plate for 5 minutes. Resting allows the juices to redistribute so the chicken remains moist when sliced.

While the chicken rests, warm the cooked brown basmati rice in a small saucepan over low heat just until heated through (or in the microwave for 45–60 seconds). Toss the warm rice with the thinly sliced red onion, a pinch of salt, a grind of black pepper, and the remaining lemon-oregano mixture (reserve a tablespoon of the sauce to finish). Tossing the warm rice with onion softens the onion slightly and lets the lemon and oregano penetrate the grains for depth of flavor.

Slice the rested chicken across the grain into 1/2-inch slices. Arrange a bed of herbed brown basmati rice on the plate, fan the lemon-oregano chicken slices on top, and spoon any pan juices over the chicken. Add the roasted Brussels sprouts alongside, and finish everything with a sprinkle of chopped fresh parsley and the reserved tablespoon of lemon-oregano sauce. The final drizzle brightens and ties the components together visually and flavor-wise.

Taste and adjust: add a pinch more salt, a squeeze of lemon, or an extra grind of black pepper if desired. Serve immediately while the chicken is warm and the sprouts are crisp-tender.