We originally used this method in the Field Kitchen for new potatoes in the summer, then found that it works brilliantly for carrots and Jerusalem artichokes too. It’s a nifty technique that seals in the flavour and lets the veg cook in its own moisture. You’ll need baking parchment and a stapler.
To make the bag, spread out a rectangle of baking parchment, approximately 60 x 30cm, with the longer side towards you. Fold it in half from left to right. Double-fold the top and bottom ends and staple the folds closed with two staples.