Cut the egg into slices. Drain the tuna. Halve the ciabatta long and cut each half into 4 triangles.
Mix the crème fraîche with mayonnaise and garlic and brush the ciabatta triangles with it.
Eight the tomatoes and cut the onion into wafer-thin slices. Top the ciabatta with tuna, egg slices, tomatoes, onions and olives. Sprinkle with cheese.