01 - Fill a small saucepan with water and bring to a rolling boil. Gently lower the eggs into the water and cook for 8 to 10 minutes until hard-boiled. Transfer the eggs to a bowl of ice water to cool, then peel and slice into rounds.
02 - While the eggs cook, place the bread slices in a toaster and toast until golden brown and crisp.
03 - Halve the avocado, remove the pit, and scoop the flesh into a small bowl. Mash lightly with a fork, then season with fresh lemon juice, sea salt, and black pepper to taste.
04 - Spread the seasoned mashed avocado evenly over each slice of toasted bread.
05 - Slice the tomato into thin rounds and layer them over the avocado spread. Arrange the sliced hard-boiled egg on top of each toast.
06 - Finish with a sprinkle of chopped chives or parsley and red pepper flakes if desired. Serve immediately while the toast is still warm and crisp.