Prep and season the chicken: Pat the chicken breasts dry with paper towels (drying helps the surface brown). Lightly flatten them to even thickness if one breast is much thicker — use a meat mallet or rolling pin inside a zip-top bag to 1 in (2.5 cm) thickness. Season both sides with 1 tsp salt and 1/2 tsp black pepper. This ensures even cooking and a seasoned interior.

Crisp the bacon: Place the chopped bacon in a cold skillet and turn heat to medium. Cooking bacon from cold lets the fat render slowly and makes it crispier with less sputter. Cook, stirring occasionally, until deep golden and crisp, about 8–10 minutes. Transfer bacon to a paper-towel-lined plate to drain. Reserve 1 tablespoon of the bacon fat in the pan for extra flavor when searing the chicken (or discard and use olive oil if you prefer).

Make the dressing (while bacon cooks): In a small bowl whisk together 2 tbsp olive oil, 1 tbsp apple cider vinegar, minced garlic, 1 tsp Dijon mustard, 1/4 tsp salt and a generous grind of black pepper. Whisking emulsifies the oil into the vinegar, creating a glossy dressing that clings to leaves and components. Taste and adjust — a tiny pinch of sugar or a drop of honey can round the acidity if needed.

Reheat or finish the roasted butternut squash (if it’s already roasted as noted): Warm the 150 g diced roasted butternut in the skillet with the reserved bacon fat or 1 tsp olive oil over medium heat for 2–3 minutes until heated through and slightly caramelized on edges. Reheating releases roasted sugars and improves texture. Transfer to a plate and keep warm.

Sear and finish the chicken: Heat a heavy skillet or grill pan over medium-high heat until shimmering. Add 1 tsp olive oil or the reserved bacon fat. Place the chicken in the pan and do not move it for 2–3 minutes — this initial contact creates a golden crust through the Maillard reaction, which adds flavor. Flip and reduce heat to medium; continue cooking until an instant-read thermometer reads 74°C (165°F) in the thickest part, about another 5–8 minutes depending on thickness. Total cook time depends on thickness — aim for juicy, not dry.

Rest and slice the chicken: Transfer chicken to a cutting board and rest for 5–7 minutes. Resting lets the juices redistribute; slicing immediately will cause those juices to run out. Slice the breasts thinly against the grain to maximize tenderness.

Assemble the salad: In a large bowl combine the 6 cups mixed greens and the thinly sliced 1/4 red onion. Add the warm roasted butternut and crisp bacon. Toss gently with half the dressing to lightly coat — overdressing wilts leaves and can make the salad soggy, so start with less and add more to taste.

Plate and finish: Divide the dressed greens between two plates. Fan the sliced warm chicken over the salad, arrange avocado slices to one side, and scatter any remaining roasted butternut. Spoon any reserved dressing or a little extra olive oil over the avocado to prevent browning. Finish with chopped parsley, a few cracks of black pepper and flaky salt if desired. Serve immediately so the contrast between warm chicken and cool greens is at its best.