Poblano and Cheese Empanadas

Name: Poblano and Cheese Empanadas
Ingredients: 1 tablespoon olive oil; 1 tablespoon unsalted butter; 4 poblano chili peppers (deseeded and cut into 1/2 inch strips); 1/2 medium yellow onion (cut into thin slices); 3/4 cup corn (canned or frozen); 2 teaspoons chicken bouillon; 1/2 teaspoon ground cumin; 1/2 teaspoon salt; 1/2 teaspoon black pepper; 1/2 cup cream cheese (or sour cream); 1/2 shredded manchego cheese (or shredded Mexican blend cheese); 15 empanada dough sheets (such as Goya brand); 1 large egg (beaten); 1 tablespoon water (plus more sealing empanadas)