Ingredients:
• 1/4 cup plus 2 tablespoons balsamic vinegar, divided
• 1/2 cup plus 2 tablespoons extra virgin olive oil, divided
• 1/4 cup Dijon mustard
• 2 tablespoons brown mustard
• 2 tablespoons honey
• 2 tablespoons water
• 1 teaspoon salt
• 1 pound boneless skinless chicken breast
• 1/2 pound portobella mushroom, sliced
Directions:
• In a small bowl, combine 1/4 cup balsamic vinegar, 1/2 cup olive oil, mustard, honey, water and salt. Whisk together until smooth.
• Place chicken pieces in a large zipper-top plastic bag and pour half of the sauce over the chicken, making sure all pieces are evenly covered.
• Refrigerate, covered, for 2 to 24 hours. Reserve the remaining half of the sauce separately.
• In a bowl, whisk together 2 tablespoons balsamic vinegar and 2 tablespoons oil.
• Add portabella slices and toss to combine. Set aside mixture for at least 15 minutes so mushrooms can marinate.
• Bring reserved half of the sauce to a boil, then reduce heat. Keep warm.
• Sauté mushroom slices with their marinade in a small sauté pan over medium-high heat until soft, about 3 minutes. Keep warm.
• Remove the chicken from the marinade. Using tongs, wipe the grill grate with a paper towel saturated with vegetable oil.
• Grill the chicken just until cooked through, 3 to 4 minutes per side.
• Serve hot, topped with warmed sauce and sautéed mushrooms.
