Heat 1 teaspoon olive oil in a medium skillet over medium heat. Add the thinly sliced onion and bell pepper and sauté until softened and beginning to brown, about 5–7 minutes. Remove from heat and set aside to cool slightly.

Season chicken

In a bowl combine the shredded cooked chicken with ground cumin, smoked paprika, salt, and black pepper. Stir in the sautéed peppers and onion and the minced cilantro until evenly distributed.

Combine cheeses

In a separate bowl mix the shredded cheddar and Monterey Jack so the cheese is ready for assembly.

Assemble & Cook

Heat a large nonstick skillet or cast‑iron pan over medium heat. Add 1 tablespoon butter and allow it to melt, swirling to coat the pan.

Place one flour tortilla in the skillet. Sprinkle about 3/4 cup of the cheese mixture evenly over the tortilla, leaving a 1/2 inch border. Distribute about 1/2 cup of the seasoned chicken and vegetable mixture over half of the tortilla. Top the filling with another 1/4 cup cheese (this helps the top tortilla stick).

Fold the tortilla in half over the filling to create a half‑moon quesadilla. Press down gently with a spatula. Cook for 2–3 minutes, until the underside is golden brown and the cheese begins to melt.

Add another 1/2 tablespoon butter to the pan if needed, then carefully flip the quesadilla and cook the other side 1.5–3 minutes until golden and the cheese is fully melted. Adjust heat to prevent burning.

Transfer the cooked quesadilla to a cutting board and let rest 1 minute, then cut into 3 wedges with a sharp knife or pizza cutter. Repeat the process with the remaining tortillas and filling, adding more butter as needed (total butter used about 2 tablespoons).

Serve

Arrange quesadilla wedges on a platter. Serve warm with sour cream, salsa, avocado slices (or mashed avocado), and lime wedges on the side. Squeeze lime over the quesadilla as desired.

Optional: garnish with extra chopped cilantro or a drizzle of hot sauce. Enjoy immediately for best crispness.