Cut red potatoes into 1/4 in. half moons.
Boil potatoes 10-15 min until almost cooked through.
Saute onions and sausage in oil until browned. Remove from pan.
Add potatoes to skillet (with some extra oil). Brown potatoes.
Return sausage-onion mix to skillet, along with sauerkraut.
Add cream and mustard. Stir and heat until thickened. Serve immediately.