Prepare the chicken: Place each chicken breast between two sheets of baking parchment and gently flatten to an even thickness (about 2cm) using a rolling pin or the base of a heavy pan. Pat them dry with kitchen paper — dry chicken sears better. Season generously on both sides with salt and pepper.

Sear the chicken: Heat the olive oil in a large frying pan over medium-high heat until it shimmers and a drop of water sizzles on contact. Lay the chicken breasts in the pan — you should hear a satisfying sizzle. Cook for 4–5 minutes without moving them, until the underside is deep golden brown and releases easily from the pan. Flip and cook for another 3–4 minutes. The chicken should feel firm to the touch but still give slightly. Transfer to a plate and set aside.

Build the base: Reduce the heat to medium. Add the butter to the pan and let it melt, scraping up any browned bits from the bottom with a wooden spoon — those bits are pure flavour. Add the diced onion and cook for 3–4 minutes, stirring often, until softened and translucent. The onions should look glossy and smell sweet. Add the minced garlic and cook for 30 seconds until fragrant — do not let it brown.

Create the creamy sauce: Pour in the chicken stock and bring it to a gentle simmer, scraping the pan again to incorporate all the fond. Let it bubble for 2 minutes, reducing slightly. Stir in the double cream, dried thyme, and paprika. If you prefer a thicker sauce, whisk the plain flour with 2 tablespoons of cold water to make a slurry, then stir it into the simmering sauce. Cook for 2–3 minutes until the sauce thickens enough to coat the back of a spoon — it should look velvety and smell rich and savoury.

Smother and finish: Return the seared chicken breasts to the pan, nestling them into the sauce. Spoon some sauce over the tops. Reduce the heat to low, cover the pan with a lid, and let everything simmer gently for 8–10 minutes. The sauce will bubble softly around the chicken. Check the internal temperature with a thermometer — it should read 74°C. The sauce will have darkened slightly and thickened further.

Rest and serve: Remove the pan from the heat and let the chicken rest in the sauce for 5 minutes. This rest time allows the juices to redistribute, ensuring every bite is tender. Sprinkle with fresh parsley before serving. The final dish should look glossy, with the chicken coated in a creamy, speckled sauce.