Hard-boil the eggs. Remove the shells, cut eggs crosswise in rather thick slices. Cut onions into very thin slices. Separate them into rings, cover them with boiling water and boil rapidly ten minutes; drain, then cover them with fresh water and boil until they are tender; drain again, but save the water. Now mix the eggs and onions carefully, without breaking. Put butter and flour into a saucepan. Mix. Add nutmeg, black pepper, lemon juice, and a half-pint of the water in which the onions were boiled. Bring to the boiling point, add cream; then add the eggs and onions. When thoroughly hot, dish them in a conical form, garnish with triangular pieces of toast, and serve.