These are giant baked Yucatecan tamales. You really should get the Yucatan cookbook and make these from that recipe, but here's a simplified version. They do taste noticeably different if you bake them in banana leaves, but you can use aluminum foil if you can't find banana leaves. I actually find frozen banana leaves to be easier to work with and you can find them in Asian or Latino groceries in the US. (ETA later than these are great with turkey too. Our leftover Thanksgiving turkey and broth went into making lots of these tamales.)
For 6 large tamales you'll need about two cups of cooked shredded chicken, 1 kilo of fresh masa (or reconstituted), about 2 cups of achiote sauce, and a bit of onion and tomato. I think it's worth making a lot of sauce and freezing it because you can make baked or steamed tamales with it, or colados. So this recipe is for a lot of sauce. If you have the chicken and sauce in the freezer, you can put these together in about 30 minutes. They bake for 90 minutes with no attention from you, except flipping them halfway (which I've forgotten to do sometimes and they still were good). I have found that tamales are way more forgiving than people make them out to be. Or, more likely, that I don't have high standards.
Banana leaves aren't entirely easy to work with, but they're doable. If they're not frozen, you need to warm them up a bit to make them flexible enough to wrap food. Usually people suggest that you pass them slowly over a flame, one at a time, but that seems impractical. You can steam then, but I rinse them and lay them out in the sun to dry and warm up. It works nicely. You'll need to cut the hard rib off the side of the leaves, then cut them into rectangles about 10x16 inches. You don't want them to have holes or tears. Save largish chunks of leaves in case one of your original rectangles tears and you need to double wrap one of them. You can save the rib bits to tie them, and you can cut a leaf into strips for tying too. I have to admit I've never tied them.
For the sauce, blend 1 cup of water with one charred head of garlic (peeled and separated into cloves), 5 tablespoons of achiote paste, and one canned chipotle. Add that to 7 cups of chicken broth and heat it. Take two cups of hot liquid out and blend it with 3/4 cups fresh or reconstituted masa, then whisk it back into the broth. Try to avoid lumps. Bring to a boil, lower the heat and simmer 10 minutes. You can add a little salt if you think it needs it. That will mostly depend on the broth you used.
For the masa, use either 1/2 cup lard or 1/2 cup oil or 1/2 cup butter. Whip that with 1 tablespoon of baking powder, then slowly add the fresh masa. Add a few tablespoons of chicken broth to get it to a spackle consistency. If you accidentally add too much, it's fine.
Preheat the oven to 350/175.
Lay out your 6 pieces of softened bananas leaves and divide the masa between them (about 200 grams each). Pat the masa out into a rectangle about 7x10 inches on each of the leaves, then top each with a strip of shredded children pieces, sauce, a few thinly sliced tomatoes, and a few bits of thinly sliced onion. You'll use about 1/3 cup each of sauce and chicken on each tamale. You'll need two Romas or one larger tomato.
To fold and tie, lift one long side of the leaf to fold the masa over, then pull it back. Tuck the other side around the masa, then fold the first side back on top to make a packet. Fold the ends over and tie it all up. I just kind of wing it. Put all six on a baking sheet and bake for 90 minutes. If the masa is still soggy, wrap the test tamale up and back a little longer. They've always taken 90 minutes for me, but they can take longer.