Rare: 4 minutes on each side Med-rare: 5 minutes on each side (recommended) Medium: 6 minutes on each side Well-done: Not recommended
Substitute rump with ribeye or fillet steak.
Start by making the polenta. Heat the chicken stock in a medium saucepan until almost boiling and slowly add the polenta constantly whisking until combined. Reduce the heat to low, cover and cook for 15 minutes, whisking every 5 minutes.
Stir in the milk, butter and parmesan cheese and season to taste with salt. Spoon the polenta into a +-25cm greased dish and place in the refrigerator for about 1 hour to set. Begin the remaining steps only after the polenta has been setting for 25 minutes.
Heat the butter in a small saucepan over a medium-high heat and sauté the onion until soft and translucent. Stir in the garlic and thyme sprigs and cook for a further minute.
Add the mushrooms and cook, stirring often, for about 3 - 5 minutes until they have released most of their juices.
Stir in the beef stock and wholegrain mustard and simmer on a low heat for about 10 minutes or until the liquid has reduced and the ragout has thickened.
Pour in the cream, and once again simmer until thickened, season with salt and pepper to taste and remove the thyme sprigs before serving.
Rub the rump steaks with olive oil, salt and freshly ground black pepper. Heat a pan until smoking hot and cook the steaks to your preference (see cooking guideline above).
Leave the meat to rest for half its cooking time before slicing into thin slivers.
Remove the polenta from the refrigerator and cut into squares. Heat a few tablespoons of olive oil in a frying pan on a medium-high heat and fry the polenta squares on both sides until warmed through and golden.
Assemble each stack by layering tender steak slices and mushroom ragout onto the golden polenta squares. Serve with a garden salad or enjoy on its own.