Make pesto: Place walnuts, garlic, Parmesan, and arugula in beaker of food processor or blender; pulse to chop. Drizzle in olive oil with machine running. Season with salt and pepper. (Pesto can be refrigerated for a day, or frozen.)
Heat grill over medium-high heat. Season chicken breasts with salt and pepper. Grill for about 5 minutes per side. Reserve on plate.
Heat large sauté pan over medium heat. Butter one side of each ciabatta slice. Place 4 slices, butter-side down in pan and top each with 1 tablespoon pesto, 1/4 cup dried cranberries, chicken breast, and 2 ounces Gorgonzola. Top each with another tablespoon of pesto and ciabatta slice, butter-side up. Grill to golden on both sides, turning sandwiches once.
- 1 cup walnut halves or pieces, toasted
- 1 clove garlic
- 1/4 cup Wisconsin Parmesan cheese, grated
- 8 ounces arugula
- 1/2 cup extra virgin olive oil
- Salt and pepper
- 4 boneless, skinless chicken breasts
- 6 tablespoons butter, at room temperature
- 8 slices of ciabatta bread
- 1 cup dried cranberries
- 8 ounces Wisconsin Gorgonzola cheese