The phrase usually refers to a specific marketing campaign by , the company famous for Cup Noodles. They have a long history of collaborating with the Naruto and Boruto franchises.
When looking for this specific item, it is typically categorized under Boruto tank tops or athletic gear. boruto breakfast dart top
What made it a "Breakfast" item wasn't just the box it came in; it was the collectible nature. You couldn't buy these at Target. You had to eat the cereal. The phrase usually refers to a specific marketing