Preheat oven to 180 degrees celsius

Lay 4 string lengths out horizontally across a baking tray covered in foil (to tie together the salmon to prevent it falling apart). Take one salmon side and place it on the baking tray. Layer the beetroot, orange and lemon along the salmon side and top with the other side of salmon.

Tie the strings together and place the whole salmon in the oven for 25 minutes.