Pesselle has an "easy" errand for you: bring her 100 medicinal leeks.

The Request

Talk to Pesselle in Galaxy Hall in Jubilife Village to accept this request.

Gather Medicinal Leeks

You can find Medicinal Leeks in many areas. They are common in the Obsidian Fieldlands. Sometimes Tuli from the Ginkgo Guild sells them, as well.

Reward

After you have 100 Medicinal Leeks, talk to Pesselle in Galaxy Hall and give them to her. You will get 1 Adamant Mint and 1 Modest Mint.