Before I turn on the stove, I dice the chicken breast into small, bite-sized pieces so it cooks quickly and evenly. I also dice the bell pepper and onion at the same time so everything is ready to go. Having my ingredients prepped ahead makes the actual cooking part move so much faster.
I heat the oil in a skillet over medium heat, then add the chicken along with the taco seasoning. I let it cook for about four minutes before stirring in the peppers and onion. Everything cooks together for another five minutes or so, until the chicken is cooked through and the veggies have softened slightly.
On a clean skillet, I melt a bit of butter and lay a tortilla flat in the pan. I sprinkle cheese over half the tortilla, spoon on some of the chicken and veggie mixture, then add another layer of cheese on top. Folding the tortilla over the filling creates that classic half-moon shape.
I let the folded tortilla cook for a couple of minutes until the bottom turns golden brown, then I carefully flip it to crisp the other side. The whole process takes just a few minutes per quesadilla, and I always watch for that melted cheese peeking out the edges as my sign it's ready.
Once both sides are golden and the cheese has fully melted, I slide the quesadilla onto a cutting board and slice it into wedges. I always serve these while they're still warm, since the cheese pull is half the fun of eating them