Veg-packed cheeseburgers

Name: Veg-packed cheeseburgers
Prep time: 20 min
Cook time: 20 min
Total time: 40 min
Cuisine: American
Ingredients: 2 tbsp vegetable oil; 1 garlic clove crushed; 1 small onion finely chopped; 100g courgette grated; 1 large carrot grated; 50g mushrooms finely chopped; ¼ bunch of parsley finely chopped; 75g cheddar grated; 1 large egg beaten; 5 tbsp breadcrumbs; 250g beef mince; 4-6 burger buns; lettuce leaves; sliced tomato; sliced red onion; ketchup mustard and mayo (optional)