I got this zunda-an at a supermarket a while ago and these little mochi blocks are a kitchen staple of mine. So, anko, koshi-an, and tsubu-an = red bean paste. Shiro-an = white bean paste. Therefore, zunda-an = green bean paste! Or, edamame bean paste. Yup, the famously salty bean appetizer/snack can also be sweet. It’s not as popular as other flavours so I always grab it when i see it.
The mochi I put under the grill until it puffs up a bit and becomes soft and chewy. Hard to beat.