Grilled Burger with Red Potatoes and Garlic Mayonnaise

Name: Grilled Burger with Red Potatoes and Garlic Mayonnaise
Prep time: 35 min
Cook time: 1 h 20 min
Total time: 1 h 20 min
Yield: 6 portions
Ingredients: 2 garlic cloves; 1 pinch salt; 1 oz extra virgin olive oil; 4 oz mayonnaise; 1 tsp lemon juice; ¼ tsp ground mustard powder; 3 green onions; 2 garlic cloves; 1 ½ tsp salt; ½ tsp ground black pepper; 24 oz ground beef; 4 red potatoes; 1 red onion; 2 tsp extra virgin olive oil; ½ tsp salt; ¼ tsp ground black pepper; 8 sprigs rosemary; 6 hamburger buns