Pork Burgers with OKA cheese

Ingredients

• 1 lb. 454 g ground Quebec pork
• ½ cup 125 ml panko breadcrumbs
• 3 tbsp. 45 ml old-style mustard
• 2 tbsp. 30 ml chives, cut into ½-in. (1-cm) long pieces
• 1 tbsp. 15 ml balsamic vinegar
• 1 egg
• 4 slices of OKA cheese or smoked cheddar cheese
• 4 onion rolls, halved
• ⅓ cup 75 ml mayonnaise
• 4 leaves leaf lettuce (green or red)
• Salt and freshly ground pepper, to taste

Caramelized onions and mushrooms

• 1 tbsp. 15 ml olive oil
• 1 tbsp. 15 ml butter
• 1 large red onion, sliced
• 1 tbsp. 15 ml thyme leaves
• 2 portobello mushrooms, sliced
• 1 tbsp. 15 ml balsamic vinegar
• 1 tbsp. 15 ml chives, cut into ½-in. (1-cm) long pieces
• Salt and freshly ground pepper, to taste