Combine the cider, sugar and thyme in a 4-quart microwave-safe bowl, and stir well.
Cook, uncovered, at full power (650 to 700 watts) for 10 minutes. Stir, return to the microwave, and cook until the sugar has dissolved and the mixture has reached a full rolling boil, about 5 more minutes.
Stir the pectin into the mixture, return it to the microwave, and cook for 1-1/2 minutes.
Skim any foam off the surface, and pack the jelly into sterilized jars according to the manufacturer's directions.
Makes 1 quart.
Note: A delicate flavor - just perfect for glazing a simple lamb or pork roast.