Mash avocados with lemon juice, salt, and pepper in a bowl until creamy with some texture. Set aside.
Bring a medium pot of water to a gentle simmer. Add white vinegar.
Crack each egg into a small cup. Create a gentle swirl in the water and slide an egg in. Poach for 3 minutes. Repeat or do two at a time.
Remove poached eggs with a slotted spoon and drain briefly on a paper towel.
Spread avocado mash generously on each toast. Top each with a poached egg.
Sprinkle with everything bagel seasoning, red pepper flakes, and a handful of microgreens.