Boil the Potatoes: In a large pot, add cubed Yukon gold potatoes and cover them with cold water, sprinkling in 1 tablespoon of salt. Bring the water to a boil over high heat, then lower to medium-high and cook for 12 to 16 minutes until tender. Drain well.

Prepare for Roasting: Preheat your oven to 400°F (200°C) and line a baking sheet with foil. Toss drained potatoes with olive oil, garlic powder, salt, and pepper. Spread evenly on the baking sheet.

Roast the Potatoes: Roast potatoes for about 30 minutes, stirring halfway through. They should be golden brown and crispy on the outside.

Make the Creamy Dressing: In a bowl, combine sour cream and mayonnaise. Add scallions, dill, parsley, mustard, and lemon juice. Season with salt and pepper, mixing well.

Combine and Serve: Once potatoes are slightly cooled, add them to the dressing, gently tossing. Transfer to a serving dish and garnish with fresh herbs.