Heat 2 tablespoons butter in a medium skillet over medium. Add onion and cook, stirring occasionally, until softened, about 4 minutes. Add chorizo and saute until onion is soft and chorizo is lightly browned, about 4 minutes more. Drain excess fat and transfer mixture to a medium bowl and let cool.

Preheat oven to 350°F. Bring the water to a boil in a small saucepan. Slowly pour in cornmeal, stirring constantly. Reduce heat to medium-low and cook, stirring, until thickened, about 2 minutes. Add to sausage mixture. Stir in corn kernels, salt, and the remaining tablespoon butter, and combine well.

Whisk together eggs and cream. Stir into sausage mixture until incorporated. Pour into a buttered 2-quart souffle dish or deep-pie plate. Bake until set and top is golden brown, about 1 hour. Serve hot or at room temperature.