1Heat a small saucepan over medium heat. Add 1 tablespoon oil and cook sauerkraut, stirring often, until starting to brown, about 5 minutes. Remove from heat and cover.
2Heat remaining 1 tablespoon oil in a large frying pan. Cook sausages, turning once, until crispy on both sides, about 7 to 8 minutes total. Remove kielbasa and reduce heat to low.
3Lightly butter 1 side of each slice of bread. Build two sandwiches next to each other in warm pan, starting with one slice of bread, buttered side down; a slice of cheese; two pieces kielbasa; half the warm sauerkraut; another slice of cheese; and topping with another slice of bread that’s also spread with half the Dijon, buttered side up.
4Grill the sandwiches in the pan, covered, until crispy and golden, carefully turning once about halfway through, about 7 minutes total. Cut and serve with Russian dressing on the side, pickles and potato chips. .