Preheat oven to 425°F (220°C). Spray a 1 1/2 qt. (1.5L) casserole with vegetable spray. Prepare instant mashed potatoes according to package directions. In a pot of boiling salted water, cook cabbage until tender, stirring occasionally, about 6 minutes, drain. Cut cream cheese into small pieces and add to potatoes along with cabbage and green onions. Add Mrs. Dash® Onion & Herb and mix well. Spread potato mixture into prepared casserole and top with cheddar cheese. Bake uncovered, for 40 minutes or until heated through and golden brown on top.