Prepare the Yukon gold potatoes by peeling them and cutting them in half or quarters to make the pieces similar in size.
Boil the potato pieces in salted water until cooked through and fork tender, about 15-20 minutes.
Drain the potato pieces and return them to the pot. Add 3-4 tablespoons of butter to the cooked potatoes and mash. Season with salt and pepper and set aside.
While the potatoes are cooking, cook the bacon. In a large skillet, over medium heat, cook the bacon slices until crispy. Remove the bacon from the skillet, leaving the rendered bacon fat in the bottom of the skillet. Chop the bacon and set aside.
In the same large skillet used to cook the bacon, over medium heat, add the diced onion to the rendered bacon fat. Cook onion until translucent, about 3 minutes.
Add the shredded cabbage to the onion and stir together. Cover and cook for 5 minutes; stir, and repeat until the cabbage is wilted and tender. Season with salt and pepper.
Add half of the cooked and chopped bacon and half of the sliced green onions to the cooked cabbage. Fold to combine.
Add the mashed potatoes to the cooked cabbage, fold to combine, and heat through.
Top with the remaining cooked bacon pieces and sliced green onion and serve.