While I give you amounts for a normal-sized recipe, you can scale this up or down as much as you want. Basically colcannon is 3 parts potato (or other root veggie, like parsnip or turnip) to 1 part green thing and 1/2 part green onion. Butter and cream or milk you add to taste. If you want a store-bought, traditional version of colcannon, use potatoes and kale and scallions. If you are a forager, use any green thing -- cow parsnip, nettles, dandelions, etc -- and any wild onion. I used cow parsnip and three-cornered leeks, which grow wild all over Northern California.
2poundswaxy potatoessuch as Yukon Gold, peeled and cut into chunks
3cupsof chopped greens,loosely packed
1cupchopped green onions,scallions, ramps, etc.
1cuphalf-and-half or milk
Put the potatoes in salty water and bring to a boil. Reduce the heat and simmer until tender, about 20 minutes. When the potatoes are done, pour them into a colander and return the pot to the heat.
Add 2 tablespoons butter and the greens and onions. Saute, stirring constantly, until the greens wilt. Sprinkle some salt over the greens as they cook. Add the half-and-half and another tablespoon of butter and bring this to a simmer. Return the potatoes to the pot, turn off the heat and mash well. Add salt to taste.
To serve, put some colcannon on everyone's plate and make a little well in the center. Add a dot of butter to the well. When it melts, serve immediately.