1.Combine the lamb,carrot,onion,oregano,coriander,salt and pepper in a large bowl and mix well to combine.
2. Shape the mixture into 4 patties. Press a mushroom,stalk facing up,into the centre of each patty,pressing the mince around the top of the mushroom.
3. Heat oil in a large non-stick frying pan over medium heat. Add the bacon and cook for 4 minutes each side or until crisp. Set aside. Add the oregano sprigs to the pan and cook for 30 seconds or until crisp. Set aside. Add the burger patties to the same pan,mushroom side up,for 4 minutes. Carefully turn and cook for a further 4 minutes,or until golden and cooked through.
4. Spread aioli on cut sides of buns. Place mixed lettuce on the base. Top with bacon and burger patties and crispy oregano. Enclose with the bun lid and serve.