Roast the garlic (optional). Preheat the oven to 400°F/200°C. Remove the outer layers of the garlic head and then slice off a thin layer off the top to expose the skin of the cloves. Rub the exposed cloves with a bit of olive oil. Wrap in parchment paper and then in foil to make a packet, and then place directly on an oven rack. Roast for 35-40 minutes until soft and tender and lightly golden. Once cool enough to handle, squeeze the cloves out of the skin into a small bowl and mash with a fork.
Meanwhile, take the vegan butter out of the fridge to soften.
Start preparing the potatoes. Peel the potatoes and then rinse them in cold water. Chop the potatoes into fourths or eighths, dependent on size. Place the potatoes in a large saucepan or Dutch oven and add enough water to cover them. Add 1 tablespoon of kosher salt (or 1/2 tablespoon sea salt) and stir to combine. Bring to a boil, then reduce the heat to maintain a simmer. Simmer until the potatoes are very soft and yield no resistance when poked with a fork and almost start to fall apart, 20 to 25 minutes.
Drain the potatoes in a colander. Return the potatoes back to the saucepan. Heat over low heat for a few minutes, tossing the potatoes around to prevent them from sticking. This removes any remaining moisture in the potatoes.
While the potatoes are cooking, place the softened butter in a small bowl and add the miso paste and the mashed roasted garlic (if using). Using a fork, cream them together until well combined.
Heat a small or medium saucepan over medium-low heat. Add the miso butter and stir to combine. Once it’s almost melted, pour in the lite coconut milk. Whisk often to combine and stir until everything is melted. Season with a bit of freshly cracked black pepper. Continue heating until the mixture is very warm but not bubbling.****
Grab a large bowl. If you are using a ricer, add the warm potatoes to the ricer and pass them through into a large bowl. If you are using a potato masher or an electric handheld mixer (on low speed), mash the potatoes. Add the warm miso butter-coconut milk mixture. Fold gently with a silicone spatula or wooden spoon. Taste for seasonings, adding kosher salt and freshly cracked black pepper to taste. I usually add a bit of salt, taste, add more salt, and repeat until they're perfect.
Garnish with fresh chives and serve warm. For extra indulgent mashed potatoes, drizzle a little melted vegan butter on top of the potatoes right before serving.