Season the steaks with salt and black pepper.
Heat a frying pan until hot then add the olive oil.
Place the steaks so they are 'standing up', fat edge down, in the pan and hold them in place using a pair of tongs. Hold in place for two minutes until the fat has browned.
Turn steaks onto their sides and cook for a further 2-3 minutes. Turn over and cook for a further 2-3 minutes on the other side.
Remove from the pan and serve with the Bearnaise sauce.
To make the Bearnaise sauce, melt the butter in a saucepan.
Place the lemon juice and vinegar into another saucepan and bring to the boil.
Place the egg yolks and a splash of water into a blender or food processor.
Blend the ingredients together, slowly adding the hot butter to the mix as you go, little by little.
Continue to blend until sauce thickens.
Add the tarragon and parsley and blend to combine.