An open sandwich is a single slice of bread topped with meat, cheese, fish, vegetables, or spreads, eaten with a knife and fork rather than picked up. The format is the national lunch of Scandinavia, where Danish smørrebrød elevates it to an art of rye bread, pickled herring, roast beef, and remoulade, and it appears across Europe from German belegte Brote to Welsh rarebit’s toast-based cousin. Nutritionally, the open format naturally limits bread and encourages generous, visible toppings, which can mean more vegetables, protein, and healthy fats per bite than a closed sandwich. For caterers it offers attractive presentation and easy portion control. The single slice also suits smaller appetites and lighter meals, and wholegrain bases with protein-rich toppings make a well-balanced lunch.