Rinse corn husks and soak in warm water for 1 hour. Set aside.

Add vegetable shortening to the bowl of a stand mixer fitted with the flat beater attachment. Mix on medium speed for 8 minutes. Mixture should look like meringue. Add masa harina, baking powder and salt. Mix on medium speed until mixture resembles wet sand, about 5 minutes.

With mixer at slow speed, add warm broth in a slow stream. Continue mixing for 12 minutes.

Add carrots, squash, onion and watercress and mix at low speed for 5 minutes.

Lay husk on a large plate or flat surface, pointy side towards you. Spread approximately 1/2 cup of mixture on the flat side down to the center. Place a strip of cheese in the middle. Fold sides of husk towards the middle and fold pointy side of husk up. Repeat with remaining husks until mixture runs out.

Add water to a tamale steamer to the fill line, add steamer rack and line with a few soaked corn husks. Arrange tamales upright, leaning against each other. Cover with more soaked husks and a kitchen towel. Cover with lid and turn heat on to medium high. When water begins to boil, set timer to 90 minutes. After 90 minutes, turn heat off and let rest in the steamer for 30 minutes.

Carefully remove tamales with tongs. Serve with a drizzle of Mexican crema.