Heat a large non-stick skillet over medium heat.
Place one flour tortilla flat in the skillet.
Sprinkle the shredded cheddar cheese evenly over the tortilla.
Sprinkle the shredded Monterey Jack cheese evenly on top of the cheddar cheese.
Place the second flour tortilla on top, pressing gently.
Cook for about 2 to 3 minutes until the bottom tortilla is golden brown and the cheese starts to melt.
Carefully flip the quesadilla using a spatula and cook the other side for another 2 to 3 minutes until golden brown and the cheese is fully melted.
Remove the quesadilla from the skillet and let it cool for 1 minute.
Cut the quesadilla into 4 equal wedges and serve immediately.