In a bowl, add the parsley and coriander leaves, chilli, coarsely chopped shallot, 5 tbsp olive oil, vinegar, lemon zest and juice, salt and pepper.

Using a hand blender or blender, mix the whole thing until you get the desired consistency. leaves should be properly chopped.

Peel the potatoes by cutting the round ends of each to have a flat base and to lay them on a plate.
Dip them in a saucepan filled with water and cook them with salt.
Check the cooking by planting a knife in the flesh.

Drain the potatoes and absorb the remaining water with paper towels.

Heat 2 tablespoons of oil in a frying pan, brown all sides of the potatoes.
Absorb excess oil with paper towels.

After leaving the rump steak at room temperature for 30 minutes, massage the meat with olive oil, salt on each side. (The pepper is reserved for the end because it tends to burn when cooked).

In a hot enough frying pan, cook the rump on one side for 2 minutes and turn over.
After 2 minutes, While tilting the pan, melt 2 dabs of butter on the side and drizzle the steak with it several times for a juicy meat.
Cook until cooked through.

For a better control for the cook place a thermometer in the centre of the meat (50-52 degrees for medium rare, 53 to 58 degrees for slightly pink and beyond for well-cooked).
If you do not have a thermometer, press the meat with your finger, for a slightly pink cooking, the meat should not show resistance.

Add pepper at the end of cooking.
Do not cut the meat for 4-5 minutes to retain the juice.