Begin by washing the baby potatoes thoroughly. Place them in a large pot and cover with water. Bring to a boil over high heat and cook for about 15-20 minutes, or until the potatoes are fork-tender.
Drain the potatoes and let them cool for a few minutes. Once they are cool enough to handle, gently smash each potato with the bottom of a glass or a fork, being careful not to break them apart completely.
In a small bowl, whisk together the olive oil, lemon juice, lemon zest, black pepper, garlic powder, onion powder, and salt until well combined.
Drizzle the dressing over the smashed potatoes and toss gently to coat.
Add the chopped parsley and green onions, mixing until evenly distributed.
Serve immediately or refrigerate for at least 30 minutes to allow the flavors to meld before serving.