Place chicken ingredients in a bowl and mix to coat chicken.
Heat oil in a frying pan over high heat. Add onion and garlic, cook for 1 minute. Add red and green bell peppers and cook for 2 minutes until starting to soften. Transfer into a bowl.
Return skillet to the stove. Add chicken and cook until browned. Add chicken to the same bowl. Set aside until the filling cools (to speed it up, cover and refrigerate, and/or spread out on plate).
Preheat the oven to 220C.
Spray the baking tray lightly with olive oil. Heat in the oven while you assemble the quesadillas.
Divide the filling between the tortillas, covering half the surface. Top with cheese. Fold in half and press down gently but firmly.
Remove baking tray from oven. Transfer quesadillas onto the tray.
Bake for 8 minutes. Then turn the quesadillas (over the folded edge) then press down with the egg flip. Bake for a further 8 minutes or until the surface is crispy.
Remove from the oven and serve immediately!