Preheat oven to 425.
First, cut the pepper off of the stem. Next, slice thin ½” strips of pepper. Lastly, chop each strip into cube-sizes. The result should be ½” thick squares. Leave to the side.
Warm a skillet on the stove at medium heat with 1 teaspoon oil.
Sauté the peppers for a few minutes until some browning develops.
Add carnitas to the pan and stir to warm, about 1-2 minutes.
Turn heat to low and add cooked rice and frozen corn to the pan. Gently stir to combine and cook until ingredients are warmed through, about 2-3 minutes.
Spray a 9x11 or 9x13 baking dish with cooking spray. Cover the bottom with ¼ cup enchilada sauce.
Place a tortilla down on the enchilada sauce, and add one fourth of the carnitas mixture to each flour tortilla, about ½ cup of corn, rice and carnitas filling.
Roll the tortilla over, until the seam is facing down. Push the enchilada toward one side of the baking dish.
Repeat with the remaining 3 tortillas, making sure they are seam side down.
Top with final ¼ cup enchilada sauce and smooth over with a spoon. Top with shredded cheese if desired.
Bake for 15-20 minutes, until top is slightly crispy and enchiladas are completely cooked through.
For a crispier enchilada, broil for an additional 1-3 minutes, until edges are crisped.
Remove from oven and serve immediately. Serve with guacamole, sour cream, queso fresco, or cilantro.