Heat a griddle pan to smoking hot, oil the rump steaks and season with salt. Place on the sizzling pan and sear for 3-4 minutes before turning over and cooking for another 3 minutes. Season with pepper, cover in foil and set aside to rest.
In a sauce pan add the saute the garlic and rosemary until fragrant, add the cream and bring to a simmer, squeeze over the lemon and lime juice and add the zest. Simmer for about 5 minutes and season with salt and pepper.
Slice the cooked steak into 1cm slices and drizzle over the sauce.