01 - Place eggs in a saucepan and cover with cold water by about 1 inch. Bring to a rolling boil over medium-high heat, then cover the pan, remove from heat, and let stand for 9 to 10 minutes. Transfer eggs to a bowl of ice water to cool completely, then peel and slice into rounds.
02 - Toast the bread slices in a toaster or on a skillet over medium heat until golden brown and crisp on both sides.
03 - While the bread toasts, halve the avocado and remove the pit. Scoop the flesh into a mixing bowl and add the lemon juice, salt, and black pepper. Mash with a fork to your preferred consistency — creamy with some chunky texture works best.
04 - Divide the mashed avocado evenly between the two warm toast slices, spreading it to the edges in an even layer.
05 - Arrange tomato slices over the avocado, then top each toast with the sliced hard-boiled eggs. Drizzle with olive oil if using, and finish with a sprinkle of salt, pepper, fresh herbs, and crushed red pepper flakes.
06 - Serve immediately while the toast is still warm and crisp.