- Brush the chicken with half the pesto.
- Preheat the barbecue to medium-high heat or use a ridged pan to cook on the stove. Grill the chicken, peppers and onion for 10 to 15 minutes until the chicken is no longer pink and the vegetables are grilled on both sides. Season with salt and pepper.
- Thinly slice the chicken, peppers and onion, as desired. Set aside.
- Spread the inside of the buns with the remaining pesto. Add the chicken, bell pepper, onion and cheese. Adjust the seasoning. Close each loaf.
- Cook the panini on the grill or ridged skillet for about 5 minutes or until the cheese is melted. Place a weight like a cast iron skillet or a brick wrapped in aluminum foil on the panini to flatten them.
- Flip halfway through the cooking process to mark the bread. Cut each panini on the bias and serve with Dijonnaise.
Dijonnaise is a mixture of mayonnaise and Dijon mustard that is easy to replicate at home by mixing the two mentioned ingredients, to taste.