Place the bread slices in the air fryer basket. Lightly spray them with oil or brush with a little olive oil. Air fry at 360°F (180°C) for 2 to 3 minutes until they are lightly golden and slightly crisp.
While the bread is pre-toasting, cut the avocado in half and remove the pit. Scoop the flesh into a small bowl. Add a pinch of salt, pepper, and a squeeze of lemon juice. Mash it with a fork until it reaches your preferred consistency.
Spread the mashed avocado evenly over the pre-toasted bread. Use the back of a spoon to create a small “well” or indentation in the center of the avocado mash. This will help hold the egg in place.
Carefully crack one egg into the well on each slice of toast. If you are worried about the egg sliding off, you can crack it into a small ramekin first and then gently pour it onto the avocado.
Place the assembled toasts back into the air fryer basket. Cook at 350°F (175°C) for 5 to 7 minutes. Check at the 5-minute mark; cook longer if you prefer a set yolk or stop early if you like it runny.
Carefully remove the toast using a spatula. Sprinkle with red pepper flakes, extra salt, and pepper before serving immediately.