Prepare the sliced beef:
Heat a non-stick pan or grill with butter.
Cook the beef for about 2-3 minutes per side for rare or 4-5 minutes per side for medium doneness.
Let it rest for a few minutes, then slice thinly and season with a pinch of salt.

Prepare the fresh ingredients:
Wash and dry the iceberg lettuce leaves, then arrange them as a base in a bowl or deep plate.
Peel the mandarin and separate the segments.
Chop the tomato and avocado into small pieces.
Rinse the blueberries.

Assemble the bowl:
Place the sliced beef in the center of the lettuce leaves.
Arrange the mandarin segments, blueberries, avocado, and tomato around the beef.

Final seasoning:
Sprinkle with black pepper and various spices.

Serve and enjoy:
Serve immediately to enjoy the freshness and perfectly balanced flavors of this bowl.