Lobster Tamales with Poblano-Corn Sauce

2 cups chicken broth1 cup thawed corn kernels, fresh or frozen
4 cups masa harina
1 3/4 teaspoons baking powder
1 3/4 teaspoons salt
6 ounces lard
24 dried corn husks, soaked in warm water for 10 minutes, drained and patted dry
1 1/2 pounds cooked lobster meat, cut into 1/2-inch pieces

Sauce:

3 tablespoons unsalted butter, divided
1 medium white onion, diced
2 garlic cloves, minced
2 tablespoons all-purpose flour
1 cup half and half
1 cup heavy cream
1 large poblano pepper, roasted, peeled, seeded and chopped
1 cup thawed corn kernels, fresh or frozen
2 tablespoons fresh cilantro, chopped
1 teaspoon grated lime zest
1/2 teaspoon salt
1/4 teaspoon ground black pepper

1. To make the tamales: puree the chicken broth and corn in a blender. Combine the masa harina, baking powder and salt in a medium bowl; cut the lard into the mixture with a pastry blender or two forks until the mixture resembles coarse meal. Pour in the broth-corn mixture; stir until a soft dough forms.
2. Working with one husk at a time, place 3 rounded tablespoons of the masa dough in the center of the husk; press the dough down into a 4 x 3-inch rectangle. Top the masa with lobster and fold the left-hand side of the husk towards the center. Fold the tip (or point) end of the husk up towards the center. Fold the right-hand side in toward the center, overlapping with the left. Fold the top end down over the center of the husk to close the tamale; tie with kitchen string to secure. Repeat with the remaining masa and lobster.
3. Place the tamales vertically in the steamer insert of a Dutch oven with steamer insert. Bring 6 cups water to a boil in the Dutch oven over medium heat. Place the steamer insert into the pan and cover. Steam 60-65 minutes, adding more water if necessary, until the dough is firm. Let stand 10 minutes before serving with sauce.
4. To make the sauce: melt 2 tablespoons of the butter in a large nonstick skillet over medium heat. Add the onion and garlic; cook, stirring occasionally, until the onion just begins to brown, 6-7 minutes. Sprinkle the flour over the onion and cook, stirring, 1 minute. Whisk in the half and half and heavy cream and cook, stirring, until the mixture thickens, about 4 minutes. Add the poblano pepper and cook 1 minute. Transfer to a blender and puree.
5. Melt the remaining 1 tablespoon butter in the skillet. Add the corn and cook until lightly browned, about 3-4 minutes. Pour in the poblano mixture and cook until heated through, about 1 minute. Remove from the heat and stir in the cilantro, zest, salt and pepper.
6. To serve: open tamales and drizzle the filling with the sauce.