Microwave on high 30 seconds; you should see bits of solid egg floating in uncooked part. Stir gently (this will help egg cook evenly) and microwave again 30 seconds or until egg puffs up dramatically. Add cheese and continue to microwave until egg is just set and cheese is melted, 15–30 seconds. Using a small spatula, transfer egg mixture to bottom toast slice. Top with avocado, drizzle with hot sauce or pesto, then top with remaining toast slice. Serve immediately.