Leave the dough, covered, in a warm place for 8-24 hours depending on the season and your taste. An airing cupboard, sunny spot or, in the winter, close proximity to a radiator or fire will all work
Make The Filling
Top and tail the courgette(s) and cut in 4 lengthwise. Remove the seeds with a sharp knife and discard. Cut the courgettes into batons no longer than the intended lengths of your tamales. Set aside
Gently soften the onions in the oil for 5-10 minutes, add the garlic and fry for another couple of minutes. Add your fresh or canned chopped tomatillos or ripe red tomatoes
Make a simple reduction as you would with a classic tomato sauce. Near the end of cooking add the chopped corander and/or other fresh green herbs of your choice
Allow the sauce to cool, then refrigerate until ready to use
Meanwhile, toast the green, hulled pumpkin seeds to release their flavour, but without browning. Cool for a few minutes then grind them coarsely, either by hand in a rough mortar and pestle or with an electric coffee grinder / mini-chopper. Set aside.
Prepare The Corn Husks
Soak corn husks for an hour or longer until they are really soft and pliable. You'll need 2-3 husks per tamal.
Assemble Your Tamales
Lay a few husks on your work-top or table, pointed side towards you. Spread the dough to rather less than 1/2-inch thick over the top 2/3 of the husk, leaving a small margin at the sides.
Spoon over some sauce, sprinkle with pumpkin seeds and top with courgette. Try not to overfill your tamales
Fold in the sides, making sure they overlap, then fold the lower part of the corn husk to seal the bottom. The blunt, top end of the tamal remains open to allow for expansion during steaming. Tie your tamales with strips of spare corn-husk or some fine string
Place the tamales open side up in a steamer. Cover and cook for around an hour, topping up the water as necessary
Notes
For a truly exotic touch and extra Mexican authenticity try using strips of nopal cactus in place of courgettes.Unlike the prickly pear to which they're related, nopales have edible paddles. They are available tinned or in jars from Mexican food suppliers. I have never seen fresh nopales in Europe. Please prove me wrong. Or I'll be forced to grow my own - in a tub, on my roof terrace. . . ?