Season the chicken and get the pan hot. Pat the chicken breasts dry with kitchen paper — this is crucial for a good sear. Season both sides generously with salt, pepper, and a pinch of dried oregano. Heat a large, heavy-based skillet over a medium-high flame until it’s just beginning to smoke. Add the olive oil and swirl the pan. You should hear a satisfying sizzle as the oil hits the metal. Lay the chicken pieces in the pan, leaving a finger’s width between each piece. Let them cook undisturbed for 4–5 minutes. Listen for a steady, gentle hiss; if it goes quiet, the pan has cooled too much. Look for a deep golden-brown crust forming on the underside.

Flip and finish the chicken. Turn the chicken over with tongs. The cooked side should be a rich amber colour with crisp edges. Cook for another 4 minutes, then reduce the heat to medium-low. Add a splash of chicken stock to the pan (about 2 tablespoons) and cover with a lid. Steam the chicken for 2–3 minutes until it’s cooked through — the internal temperature should reach 74°C. The steam will smell savoury and slightly nutty. When you pierce the thickest part, the juices should run clear, not pink. Transfer the chicken to a cutting board and tent loosely with foil. Do not clean the pan!

Build the sauce base. In the same skillet, reduce the heat to medium. Add the reserved sun-dried tomato oil and the diced onion. Stir frequently, scraping up any browned bits from the bottom of the pan — these are packed with flavour. Cook for 3–4 minutes until the onion turns translucent and soft. The onion will release a sweet, almost caramelised aroma. You should see it become glossy. Add the minced garlic and the chopped sun-dried tomatoes. Cook for 1 minute more, stirring constantly, until the garlic is fragrant but not coloured.

Add the liquid ingredients. Pour in the chicken stock, using a wooden spoon to lift any remaining fond from the pan. Bring the mixture to a gentle simmer. Let it bubble for 2–3 minutes, reducing slightly. The stock will darken and thicken, and the kitchen will smell intensely of tomato and herbs. You’ll see the liquid become less watery and more syrupy around the edges of the pan. Stir in the double cream, dried oregano, and red pepper flakes if using. Turn the heat down to low.

Cook the pasta. While the sauce simmers, bring a large pot of salted water to a rolling boil. Add the penne and cook according to the package instructions until al dente (usually 10–12 minutes). Just before draining, dip a mug into the pot and reserve 250ml of the starchy pasta water. The water should look cloudy and feel slightly slippery between your fingers. Drain the pasta well, but do not rinse it.

Combine everything. Slice the rested chicken into thick strips, about 2cm wide. Add the drained penne directly to the skillet with the sauce. Toss gently with tongs, coating every piece of pasta. If the sauce seems too thick, ladle in the reserved pasta water a splash at a time, stirring, until it loosens to a silky consistency that coats the back of a spoon. The sauce should look glossy and move slowly, not runny. You’ll see it cling to the penne tubes as you toss. Gently fold in the sliced chicken and half the grated Parmesan. Taste and adjust seasoning with salt and pepper.

Rest and serve. Remove the skillet from the heat. Let the dish sit for 2–3 minutes — this allows the sauce to settle and the flavours to marry. The pan will cool slightly, and the sauce will thicken a touch more as it rests. The aroma will be rich, creamy, and deeply savoury. Serve directly from the skillet or transfer to a warm serving bowl. Top with the remaining Parmesan and a generous scattering of torn fresh basil.