Halve any smaller potatoes and quarter larger ones so they’re all roughly the same size. Add to a medium pot, cover with water, and add a generous pinch of salt. Place over a high heat on the stove and bring to a boil.
Once boiling, turn the heat down to simmer and cook for 10-15 minutes until the potatoes are fork-tender then drain well.
Return the potatoes to the pot and mash with a potato masher until fluffy and free from lumps, or use a potato ricer for a smoother result.
Place the olive oil in a small skillet over a medium heat. Once hot, turn the heat down to low, add the garlic, and heat for 1-2 minutes to gently cook. You don’t want the garlic to brown, just soften slightly.
Add the drained white beans and a splash of the cashew milk to a bowl or jug and blend with a stick blender until smooth.
Pour the warm garlic oil into the potatoes and mash together. Mix in the pureed white beans.
Pour in the cashew milk, starting with ½ cup and adding more as needed to reach your desired consistency, and gently mix it in until combined.
Taste and season with salt then serve.