Steak and Potatoes with Balsamic Cranberry Pan Sauce

1 yellow onion
1/4 oz Rosemary
16 oz Potatoes
4 oz Red Cabbage
1 tsp Mustard Seeds
2 TBS White Wine Vinegar
12 oz Sirloin Steak
1/2 TBS Sou Sauce
4 tsp Cranberry Jam
3 TBS water
2 tsp Olive Oil
1 TBS oil
1 tsp sugar

Preheat oven to 425 F. Thinnly slice onion. Cut potatoes into 1 inch thick wedges. Toss potatoes on baking sheet with drizzle of olive oil and rosemary. Season with salt and pepper. Roast until lightly browned and crisp (30 - 35 minutes). Heat oil in pan on medium heat. Add onion and cabbage and cook until softened (5 minutes), tossing. Add mustard seeds and cook until they start to pop. Stir in white wine vinegar, sugar and a pinch of salt. Reduce heat to low, cover and cook until cabbage is tender (10 minutes). While cabbage cooks, heat oil in another pan over medium high heat. Pat steak dry with a paper towel, season all over with salt and pepper. add to pan and sear until browned and cooked to desired doneness (4 - 7 minutes per side). Remove and set aside to rest. Add Balsamic Vinegar, soy sauce, cranberry jam and water to same pan over medium heat. Stir to combine. Let simmer until reduced to a syrupy consistency (2-3 minutes). Remove from heat. Thinly slice steak against the grain. Drizzle glaze over steak and serve.