Prepare the patty mix. In a large bowl, combine the beef mince, half of the chopped onion, the minced garlic, breadcrumbs, beaten egg, tomato purée, dried thyme, salt, and pepper. Use your hands to mix gently until everything is just combined — overmixing will make the patties tough. You’ll feel the mixture becoming slightly sticky but still light.

Shape the steaks. Divide the mixture into 4 equal portions. Shape each into an oval patty, about 2 cm thick. Press a small indent into the centre of each patty with your thumb — this stops them from puffing up into a dome as they cook. You should see a neat, uniform shape that will brown evenly.

Brown the patties. Heat the oil in a large, heavy-based skillet over a medium-high heat. Once the oil shimmers and a tiny piece of bread sizzles on contact, carefully lay the patties in the pan. Cook for 4–5 minutes on the first side, until the underside is a deep, rich brown and the edges look opaque. Flip them gently — you’ll hear a satisfying sizzle — and cook for another 3–4 minutes. Transfer the patties to a plate; they won’t be cooked through yet, and that’s fine.

Sauté the mushrooms and onions. In the same pan, add the remaining chopped onion and the sliced mushrooms. There should be enough residual fat in the pan; if it looks dry, add a tiny splash more oil. Cook over a medium heat for 6–8 minutes, stirring occasionally. You’ll see the mushrooms release their liquid, then that liquid evaporates, and the mushrooms begin to turn a lovely golden brown. The kitchen will smell deeply savoury at this point.

Make the gravy base. Sprinkle the flour over the cooked mushrooms and onions. Stir constantly for 1–2 minutes — you’ll see the flour disappear into the fat and turn a pale biscuit colour. This step is crucial; it cooks out the raw flour taste and ensures a silky gravy.

Build the gravy. Slowly pour in the beef stock while whisking continuously to prevent lumps. Add the Worcestershire sauce. Bring the mixture to a gentle simmer — you’ll see small bubbles breaking the surface, not a rolling boil. Let it cook for 2–3 minutes, stirring occasionally, until the gravy thickens enough to coat the back of a spoon. The colour will deepen to a glossy, rich brown.

Finish cooking the steaks. Return the browned patties to the pan, nestling them into the gravy. Spoon some of the gravy over each patty. Reduce the heat to low, cover the pan, and simmer for 10–12 minutes. When done, the patties will feel firm to the touch but still have a little give, and the gravy will be bubbling gently around them. Stir in a knob of butter at the end if you want an extra glossy, velvety finish.