Place potatoes and water in a microwave-safe dish. Cover and microwave on high for 4 minutes or until tender; drain.
In a large skillet, sauté kielbasa and onion in oil until onions are translucent.
Add potatoes; sauté 3-5 minutes longer or until kielbasa and potatoes are lightly browned,
In a small bowl combine the brown sugar, vinegar, mustard, thyme, and pepper; stir into skillet.
Bring to a boil. Reduce heat; simmer, uncovered, for 2-3 minutes or until heated through.
Add spinach and bacon; cook and stir until spinach is wilted.