Spread butter on both sides of the bread and dry toast it on the pan

In same pan, add a little oil and break the egg into the center of the pan

Let it Cook until the whites have set, yolk should be a bit runny

Season with a sprinkle of salt and pepper

To assemble. Slice avocado lengthwise and sprinkle with lemon juice. Add on top of the toasted bread. Top the avocado with the fried sunny side up egg. Garnish with cilantro if desired