To prepare marinated Ikura, add ikura, soy sauce and mirin in a small bowl and mix all together.
Drain the Burrata cheese and place in a serving dish. Gently break open the cheese (I make a slit on top) and put the marinated ikura on top. Surround it decoratively with arugula and serve with sliced toasted baguette.
To enjoy, place burrata cheese, arugula, ikura and put a bit of yuzu kosho on top of crostini.