Some of the items on my shopping list _ chanterelle mushrooms, white asparagus, and eel _ were impossible to find.

The three foods explain which items on the shopping list were impossible to find, so they form an interrupting detail. Dashes can set off that detail: “Some of the items on my shopping list—chanterelle mushrooms, white asparagus, and eel—were impossible to find.” The matching dashes clearly mark where the added list begins and ends.

AI-written and checked against the verified answer.