In a large bowl, combine the shredded chicken, Monterey Jack cheese, salsa, ground cumin, chili powder, and garlic powder. Mix until well combined.

Lay out the flour tortillas on a flat surface. Spoon about 1/2 cup of the chicken mixture onto the center of each tortilla.

Fold each tortilla burrito-style: fold in the sides, then roll tightly from bottom to top to enclose the filling completely.

Heat about 1 inch of vegetable oil in a deep skillet or pot over medium heat until it reaches 350°F (175°C).

Carefully place the rolled chimichangas seam-side down into the hot oil. Fry for 2-3 minutes per side, or until golden brown and crispy.

Remove the chimichangas from the oil and drain on paper towels to remove excess grease.

Serve the chimichangas with sour cream, guacamole, and a sprinkle of chopped cilantro if desired.