Pierce potatoes several times. Microwave potatoes on high until just tender, 5–6 minutes. When cool enough to handle, cut potatoes in half/reserve.
In large nonstick skillet, heat 2 Tbsp. oil over medium-high heat. Add carrots and onion; cook, stirring often, until lightly browned. Add hot dogs, sauerkraut with liquid, 1⁄2 cup water, horseradish and 1⁄4 tsp. pepper. Bring to boil; reduce heat to medium-low. Cover; cook until carrots are tender, adding potatoes during last 5 minutes.
If desired, sprinkle with 1 Tbsp. chopped fresh parsley.