Place potatoes (unpeeled) in a large pot and cover with cold water. Salt lightly. Bring to a boil and continue to boil gently for 15 to 20 minutes or until fork tender. Drain and cool slightly. Peel while still warm. Slice and place in a large bowl.
While potatoes are cooking, bring 2 cups water to a boil; reconstitute bouillon cubes. Set aside.
In a large skillet, cook bacon until crisp. Spoon bacon and 1 tablespoon of bacon grease over potatoes. Add beef bouillon, onion, oil, vinegar, sugar, salt and pepper. Mix gently. Serve warm.