Remove the beef from the fridge one hour before you want to start cooking it. Season all over with salt and pepper and allow to stand at room temperature for 1 hour.
Heat your oven to 200˚C (180˚C fan-forced). Rub the beef with 1 tbsp of olive oil and place into a roasting tray. Roast for 45 minutes for rare (add an extra 15 minutes for medium-rare). Remove from the oven and allow to cool for 30 minutes. Cover the beef completely with foil and chill in the fridge overnight.
For the mayonnaise,combine the tuna,the remaining 2 tbsp of olive oil,mayonnaise,lemon juice and mustard in a food processor or blender and process to a smooth purée,adding a little water if necessary. If you prefer a chunkier mayonnaise,skip adding the water and just mix the ingredients together. With a very sharp knife,slice a portion of the chilled beef as thinly as you can and arrange it to cover a serving plate. Top with a little of the tuna mayonnaise,capers,rocket and red onion. Serve with slices of sourdough bread.
Adam's tip Frying the capers for the carpaccio gives them a different texture. Heat a ¼ cup of olive oil in a small saucepan and add two or three tablespoons of capers that have been patted dry with a paper towel. Swirl the capers in the pan for about a minute and remove with a slotted spoon.
Also try:Adam Liaw's peach melba slushies
Find more of Adam Liaw's recipes in theGood Food Favourite Recipes cookbook.