Heat oil in a six-quart pot. Add onion and sauté until soft and golden.

Add potatoes. Fill pot with water almost to the top. Add salt, garlic powder, and black pepper. Bring to a boil and boil until potatoes are fork tender.

Using a slotted spoon, remove half of the potato cubes.

Blend the remaining soup (using an immersion blender or traditional blender) and add the potato cubes back in.

Adjust seasoning to taste. For an interesting kick, add some smoked paprika.