Place the potatoes in a large pot and cover with cold water. Bring to a boil and cook until fork tender, about 10-12 minutes. Be careful not to overcook them. Drain and let cool for 15-20 minutes.
In a large mixing bowl, whisk together the mayonnaise, sour cream, ranch seasoning, garlic powder, pepper and salt until smooth.
Add the cooled potatoes, cheddar cheese, bacon and green onions to the bowl. Gently stir until everything is evenly coated.
Cover and refrigerate for at least 1 hour before serving so the flavors can blend together.
Before serving, top with additional bacon, cheddar cheese and green onions if desired.
Notes
Salt the water generously: Once the water comes to a boil, add a generous amount of salt. This helps season the potatoes to ensure a much more flavorful salad.
Check the potatoes frequently: Check your potatoes every few minutes for tenderness and cook them just until a knife easily pierces through the skin. Overcooked potatoes can become too soft and fall apart when mixed with the dressing.
Cool the potatoes before mixing: Let the potatoes cool for about 15-20 minutes after draining. Mixing them while they're still hot can cause the dressing to become runny and the cheese to melt instead of staying shredded.
Cut potatoes into even-sized pieces: Keeping the potato pieces close to the same size helps them cook evenly and gives the salad a consistent texture.
Drain and pat dry the bacon: The crispier, the better! Be sure to drain the bacon well on a paper towel before crumbling it and adding it to the salad.
Chill before serving: Refrigerating the salad for at least an hour allows the ranch seasoning to fully hydrate and gives the flavors time to blend together.
Taste before serving: After the salad has chilled, give it a quick stir and taste before serving. Add a little extra salt or black pepper if needed, since the flavors mellow as they chill.
Garnish just before serving: Add your final garnishes right before you serve for the freshest flavor and prettiest presentation.