01 - Preheat oven to 425°F. Line two baking sheets with parchment paper.
02 - Combine shredded chicken with chili powder, cumin, garlic powder, salt, and pepper in a large bowl. Toss until evenly coated.
03 - Place 4 tortillas on a flat surface. Distribute seasoned chicken, cheese, bell pepper, and green onions evenly, leaving a 1/2-inch border. Top with remaining tortillas and press gently to seal.
04 - Brush both sides of each quesadilla with melted butter or olive oil. Transfer to prepared baking sheets.
05 - Bake for 8–10 minutes, then flip and bake an additional 7–8 minutes until tortillas are golden brown and cheese is fully melted.
06 - Let cool for 2 minutes, then cut into wedges. Serve warm with salsa, sour cream, or guacamole if desired.