Chiles Rellenos de Elote con Arroz Blanco

Name: Chiles Rellenos de Elote con Arroz Blanco
Ingredients: 4 tablespoons butter or safflower oil; 1 medium white onion, finely chopped; 2 cloves garlic, peeled and minced; 3 cups fresh corn kernels; 1 1/2 teaspoons sea salt, or to taste; 3 tablespoons finely chopped epazote; 6 large poblano chiles, roasted and peeled; 1/2 pound queso fresco, cut into 6 thick slices; 2 cups Mexican crema, recipe follows; 3 ounces Manchego cheese, grated; 2 cups heavy cream; 1/4 cup buttermilk; 1 1/2 cups long grain unconverted white rice; 3 tablespoons vegetable oil; 1/2 medium white onion, finely chopped; 1 clove garlic, peeled and minced 3 1/2 cups water