In a medium-sized skillet over medium-high heat, add the oil. Add the shallots, garlic, salt and pepper, to taste, and the chorizo. Cook for 2 to 3 minutes until nicely browned. Remove the mixture from the pan to a medium bowl and allow it to cool slightly. Stir in the cheese and mix well. Stuff the jalapenos with the filling, using your fingers or a small spoon.
In a small bowl beat together the buttermilk and eggs. In a shallow dish add the flour and season with salt and pepper, to taste. In another shallow dish add the panko. Dredge the stuffed jalapenos in the flour, then in the buttermilk, and then in the panko. Repeat the last 2 steps, if needed.
In the same pan the chorizo was cooked in, add the butter. Heat over medium-high heat, then add the corn, lemon juice, salt and pepper, to taste, and the sugar, Stir together and allow to cook for 1 to 2 minutes. Add the chicken stock and allow it to come to a hard boil. Remove from heat and cool slightly. Add the corn mixture to a blender and puree until smooth. Transfer the puree to a medium-sized bowl and stir in the sour cream.
Fry the jalapenos, in batches, until golden and crisp, about 3 to 4 minute. Arrange them on a serving dish and serve with the sweet corn puree.