Truffle Steak Sandwich

1: Prepare the steak by seasoning it with salt and pepper.

2: Cook the steak in tallow until the desired doneness.

3: In a bowl, mix egg yolk with lemon juice and finely chopped garlic.

4: Slice the truffle, tomato, and caramelized onion.

5: Assemble the sandwich with steak, arugula, truffle, tomato, onion, rosemary, and thyme.