I really only have one note about this recipe, and that is to keep in mind that parsnips (like carrots) will not cook/soften quite as quickly as russet potatoes. So that’s why it’s good to cut them into smaller pieces than the potatoes and also to keep them on bottom as they cook. You also want to make sure to test a parsnip piece to make sure everything has softened enough, because if you test a potato piece, it’s possible it could be done before the parsnips, and then you’ll begin mashing and end up with a few small bits of still-hard parsnips.