Grilled Chicken Sandwich

Ingredients

FOR THE MARINADE

• 1/4 c. extra-virgin olive oil
• 1/4 c. low-sodium soy sauce 
• Juice of 1 lime 
• 1 tbsp. stone ground mustard 
• 1 tsp. chili powder
• 1/2 tsp. crushed red pepper flakes
• Kosher salt
• Freshly ground black pepper
• 4 boneless skinless chicken breasts or thighs 

FOR THE SAUCE

• 1/2 c. mayonnaise
• 3 tbsp. honey
• 3 tbsp. stone ground mustard 
• 2 tbsp. dijon mustard
• 1 tbsp. red wine vinegear 
• 1/2 tsp. hot sauce
• Pinch kosher salt
• Freshly ground black pepper

FOR THE SANDWICH

• Red onion, cut into thin rounds
• 4 hamburger buns, preferably Martin’s potato buns
• Extra virgin olive oil, for brushing 
• Romaine lettuce 

Directions

1. Step 1In a medium bowl or glass measuring cup, whisk together oil, soy sauce, lime juice, mustard, chili powder, and crushed red pepper flakes. Season with salt and pepper. Place chicken in a large resealable bag and pour marinade over. Refrigerate and let marinate for at least 2 hours. 
2. Step 2Meanwhile, make sauce: In a medium bowl, whisk together mayonnaise, honey, mustards, vinegar, and hot sauce. Season with a pinch of kosher salt and few cracks of black ground pepper. Refrigerate until ready to use. 
3. Step 3When ready to grill, heat grill over medium-high heat. Add chicken and grill until internal temperature reaches 165°, 6 to 8 minutes per side. Remove from grill and place on a plate to keep warm. Place red onion on grill and cook until lightly charred, about 3 minutes per side. Brush inside of buns with oil and grill until golden, 1 to 2 minutes. 
4. Step 4Spread honey mustard on bottom bun and top with a piece of chicken, grilled onions, and lettuce.