Place the corn husks in a bowl. Cover with boiling water. Weigh down the husks to keep them submerged. Cover the bowl and allow to hydrate for 1-24 hours. Drain 10 minutes before filling.
Mix the masa harina with the hot water and set aside to cool. Cream the butter, salt, and baking powder in a mixer. Add the masa in three additions, scraping the sides between each addition. On low speed add the stock. When the stock has been incorporated, increase the speed to medium-high and beat until a small dollop floats in cold water. 10 minutes. Cover tightly and refrigerate for 1 hour.
Lay the corn husks on a countertop. Spread 1/4 cup of the dough in a 4x4 inch square in the top center of the husk. Leave a 1/2 inch space from the dough to the top edge of the husk. Place 1/8 cup filling in the center of the dough. Fold the edges together to touch and loosely wrap the husk. Fold up the bottom portion of the husk. Tear a husk into strips and tie the tamales to secure the husks.
Place the tamales in a steamer pot. Steam over medium heat for 1-1 1/2 hours. Remove from the pot and serve with chipotle crema, cilantro, and queso fresco.