Peel eggs. Using large holes, grate eggs into a bowl. Add salt, mayonnaise,black pepper,parmesan cheese and mustard; stir to combine.
Place bread flat on work surface. Top two bread slices evenly with egg mixture.
Top with remaining bread slices.
Grease grill toaster with butter and place bread slices on the grill.
Grill for 5 minutes .Remove from the toaster and cut into slices.
Serve hot with green chutney or tomato ketchup.
