Grilled Pesto Chicken Sandwich - Martin's Famous Potato Rolls and Bread

Ingredients

• 1 Cup Fresh Pesto, prepared*
• 1/4 Cup Rice Wine Vinegar
• 1 Teaspoon Salt
• 1 Teaspoon Granulated Sugar
• 1 Pound Boneless Skinless Chicken Breasts, halved lengthwise
• 4 Martin’s Big Marty’s Rolls
• 1/4 Cup Red Onion, thinly sliced
• 2 Tomatoes, thickly sliced
• 1 Cup Baby Spinach
• 1/3 Cup Mayonnaise
• 1 Tablespoon Fresh Lemon Juice