Which borough of London has the best roast dinners?

Oh Lord Gravy, do tell us all which borough of London has the best roast dinners...

The average rating in Hammersmith & Fulham is 7.76 (12 reviews)
The average rating in Waltham Forest is 7.60 (5 reviews)
The average rating in Kensington & Chelsea is 7.48 (13 reviews)
The average rating in Hackney is 7.40 (25 reviews)
The average rating in City of London is 7.35 (11 reviews)
The average rating in Camden is 7.29 (37 reviews)
The average rating in Southwark is 7.28 (24 reviews)
The average rating in Islington is 7.26 (22 reviews)
The average rating in City of Westminster is 7.24 (39 reviews)
The average rating in Richmond upon Thames is 7.14 (9 reviews)
The average rating in Hounslow is 6.99 (4 reviews)
The average rating in Haringey is 6.92 (5 reviews)
The average rating in Tower Hamlets is 6.81 (16 reviews)
The average rating in Brent is 6.71 (3 reviews)
The average rating in Lambeth is 6.69 (16 reviews)
The average rating in Lewisham is 6.49 (8 reviews)
The average rating in Wandsworth is 6.48 (12 reviews)
The average rating in Ealing is 6.47 (4 reviews)
The average rating in Merton is 6.46 (6 reviews)
The average rating in Croydon is 6.34 (4 reviews)
The average rating in Redbridge is 6.20 (3 reviews)

Do note that I am only including boroughs where I've had 3 roast dinners or more.