Peel and dice the shallots and place in a mixing bowl, chop the thyme and add to the bowl with the sugar and vinegar and mix well. Set aside
Rinse and in needed lightly scrub the outside of the oysters in cold running water to remove any barnicles or seaweed
Fold a tea towel into 4 and with the rounded end of the oyster facing you work your way to the furthest right hand side of the oyster, this is where you insert the knife
Place the point of the knife through the seam between the lid and base of the oyster “jiggling” it as you go at about a 45 ° angle
Once the knife breaks through the surface flatten out the knife and work your way back around the shape of the oyster towards yourself finishing at the opposite side to where you began
Lift the top of the shell away from the base, using the tip of you finger scrape out and small bits of shell that have broken off
You will see a small circle in the surface of the oyster, this indicates where it is attached to the shell. Using the knife scrape away next to this indicator on the side of the shell and set aside
Repeat with the remaining oysters
Place ice cubes into a zip lock bag and crush them with a rolling pin, pour the ice onto a shallow bowl, place the oysters on top and finish with a little of the shallot dressing on each oyster