Place sugar, cream, glucose, butter and 3 tsp of sea salt in a heavy-based pan, stir over medium-heat until sugar dissolves. Increase heat to medium-high and boil until mixture reaches 118C on a thermometer (7-8 minutes). Divide among 24 lightly buttered mini-muffin moulds and stand until firm (3-4 hours).
Melt chocolate in a heatproof bowl over a saucepan of simmering water, spoon over each caramel and stand until set. Remove from moulds and store on a single layer in a baking paper-lined airtight container for up to 5 days.
Note Liquid glucose is available from select supermarkets, health food stores and cake supply stores.