Grandma s Creamy Potato Salad with Sour Cream

2 pounds red potatoes

¾ cup mayonnaise

½ cup sour cream

½ cup plain yogurt

⅓ cup thinly sliced green onion

2 dill pickle spears, chopped, or more to taste

4 ½ teaspoons Dijon mustard

4 ½ teaspoons prepared horseradish

½ teaspoon celery seed

½ teaspoon salt

½ teaspoon ground black pepper

2 cloves garlic, minced

1 dash onion salt

1 dash garlic powder

4 hard-cooked eggs, chopped

Place potatoes in a large pot and cover with salted water; bring to a boil. Reduce heat to medium-low and simmer until tender, 20 to 30 minutes. Drain and cool slightly. Slice potatoes into a large bowl.

Combine mayonnaise, sour cream, yogurt, onions, pickles, mustard, horseradish, celery seed, salt, pepper, garlic, onion salt, and garlic powder in a small bowl; mix until combined. Pour dressing over sliced potatoes and toss to coat. Gently stir in eggs.

Cover and refrigerate for 2 to 3 hours.