Quick note on recipes (in response to comment)

It wasn't the ice cream that was purple--it was the ube truffles, which I'll discuss below. I don't actually have the ice cream recipe--it came with the ice cream maker (which was not mine). Apparently, both KitchenAid and Cuisinart ice cream makers come with vegan ice cream recipes; for green tea, just use green tea powder instead of cocoa powder (but use less, because it's STRONG)l; for azuki, make vanilla ice cream and mix in a cup or so of azuki paste (azuki beans, lemon juice, sweetener).

For the truffles (I made up this recipe as I went along, so adjust the proportions and ingredients for taste and texture as you see fit):

Ingredients

Approximately 3 lbs ube (purple yam), washed/scrubbed, but not peeled
1/2 can or more coconut milk (lite is fine)
1/4 cup high-quality, unsweetened soy milk (optional, but helps cut the sweetness--make sure you don't get one with an aftertaste)
1/2 lb to 1 lb pressed, pitted dates (these add to the flavor but also to the sweetness, so go with more or less depending on your taste)
1/2 cup to 1 cup oats, finely ground (for texture and also to cut the sweetness)
1-2 tbsp bourbon, optional

1/3-1/2 cup unsweetened ground coconut
1/3 -1/2 cup hazelnuts, roasted and ground (not too finely)

Directions

Roast ube until really, really soft (maybe 375-450 degrees, for an hour or so). Let cool and remove skin; mash up or blend in a large bowl.

While the ube is roasting, mash up/separate the dates so that they blend more easily with the ube. Maybe mix them up with the coconut milk to get them separated.

Add the dates, coconut milk, soy milk, oats, and bourbon to the ube mixture and blend until smooth. Cover and chill for an hour or so.

Mix the ground coconut and hazelnuts in a bowl. Scoop out the chilled ube and roll into balls, and then roll in the coconut and hazelnuts. Stick on a plate and stick in the freezer until they're ready to serve.