Add the plant milk to a small saucepan, then slice the green onions and add them to the milk. 

Place a hot pad on a large capacity kitchen scale, then zero the weight. Put the saucepan with the milk and onions on the scale. Write down how much it weighs. Subtract 240 grams, then circle the answer. This is your target weight. (If you do not have a scale, you will have to estimate when the milk is reduced by half, and then measure it to check. I highly recommend that everyone get and use a digital kitchen scale.) My pan and milk weighed about 1,240 grams, so my target weight was 1,000 grams.

Heat the milk and onions over medium-low heat while stirring continuously, until the mixture comes to a boil. Reduce the heat, and simmer until the milk is reduced by half (and the pot reaches your target weight.) Stir every few minutes while the milk is simmering. Remembering to stir it is the only tricky part of this recipe!

Peel and cut up your potatoes while the milk is simmering. Add them to a large saucepan and sprinkle the 1 TBS of salt on top. This is just to make the cooking water salty and very little will end up in your mashed potatoes. Add enough water to cover the potatoes by at least half an inch, then cover the pan and bring the water to a boil.

While the milk is simmering, and while you are waiting for the potatoes to boil, chop up the cabbage into strips about 1 1/2″ long by 1/2″ wide. Add the chopped cabbage to a medium-sized saucepan and add an inch of water to the bottom of the pan. Cover the pan, and heat on medium-high until the water is boiling. Reduce the heat, and simmer for about three minutes. The cabbage should be softened, but not mushy. I like mine to still be a bit crunchy to give the colcannon some texture. (Remember to keep stirring the milk!)

Transfer the cooked cabbage to a colander to drain and set it aside for now.

Once the water with the potatoes is boiling, reduce the heat, and simmer for 10 to 20 minutes until your potatoes are fork tender. That means a fork should be able to easily pierce the potatoes with little resistance, but the potato pieces should still be holding their shape. (Remember to keep stirring the milk!)

Once the milk begins to cook down, turn your scale on with the hot pad in place (the scale should read zero with the pad on it), then place the pot on the hot pad and check the weight. Repeat every few minutes to see how close you are to the target weight. I was looking for 1,000 grams so this was ready. Your target weight will be different because your pot will not weigh exactly the same amount as mine does. Once it has reached the target weight, add the vegan butter, salt, and pepper. Stir until the butter melts, then set aside for now.

Remember to keep an eye on your potatoes! Once they are fork tender, drain them in a colander, then add them back to the pan. Cook for several more minutes to dry them out. Add the dried potatoes to a large mixing bowl, and beat on high speed until smooth and fluffy.

Pour in the reduced milk and onion mixture, then stir together.

Add the cooked cabbage and stir again. Your colcannon is done, but may not be hot enough depending on if your reduced milk and cooked cabbage had cooled down too much. So, if needed, heat your colcannon in the microwave until piping hot.

Serve the traditional way with lots of melted vegan butter and black pepper. Enjoy!