Roast the chile directly over a gas flame until charred, about 2 minutes. Scrap off the skin, then slice off the stem end and remove the seeds. Fill the chile with the cheese. Set aside.
Heat the oil in a deep skillet over medium-low heat until hot enough to fry the chile.
While the oil heats, prepare the tomato sauce: In a blender, puree the tomato along with the garlic and 1/2 cup water. Heat the remaining 3 tablespoons oil in a skillet over medium heat. Add the sliced onions and saute for about 3 minutes. Add the tomato mixture and a pinch of cinnamon and salt. Bring to a boil, then lower the heat and simmer for 10 minutes.
Place the egg white in a small bowl and mix with a hand mixer until it reaches a tempura consistency, 4 to 5 minutes. Add the yolk and mix again until it turns yellow. Dredge the stuffed chile in flour, then dip in egg wash. Fry in the hot oil until golden, about 15 minutes.
Place the chile on a plate and cover with tomato sauce. Top with some cheese, sour cream and the fried plantain.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
Recipe courtesy of El Rincon de Los Antojos, Cancun, Mexico