Step 1

Peel the potatoes and cut them into 2-inch pieces. Add them to a Dutch oven and cover with 1 inch of water. Bring to a boil over medium-high heat and add 2 tablespoons of salt. Boil, stirring occasionally, until the potatoes are very tender, about 15 minutes. Drain the potatoes in a colander and set aside.

Step 2

In the same Dutch oven, melt the butter over medium heat. Add the cabbage or mixture of greens, the remaining 1 teaspoon of salt, and the pepper. Cook, stirring often, until the cabbage mixture ;is softened, about 5 minutes.

Step 3

Reserve 1/4 cup of the green onions for garnish and add the remaining green onion and garlic into the cabbage mixture. Cook, stirring often, until the garlic is lightly browned, about 2 minutes.

Step 4

Reduce the heat to medium-low. Add the half-and-half and cook 2 to 3 minutes until warm. Add the potatoes, then mash and stir until the mixture is well combined. Season with additional salt and pepper, to taste.

Step 5

Transfer the colcannon to a serving dish and top with more butter, if preferred. Sprinkle with the reserved 1/4 cup green onions.