Cheap Irish Colcannon

2 ½ cups thinly sliced green cabbage

1 cup chopped broccoli

3 cups hot prepared instant mashed potatoes

4 tablespoons butter, or as needed

1 pinch garlic salt

ground black pepper to taste

Place the cabbage and broccoli in a saucepan, and fill with just enough water to cover the vegetables. Cover, and bring the water to a boil over high heat. Reduce the heat to medium, and simmer until vegetables are tender, about 5 minutes; drain.

Stir in the prepared mashed potatoes, butter, garlic salt, and black pepper.