Divide the gin between two small heatproof glasses or mugs.

Pour 100ml water into a saucepan with the rest of the ingredients, reserving one lemon slice. Heat gently over a low heat until simmering.

Strain the mixture into a jug, discard the fruit and spices, then pour the toddy over the gin in the glasses and stir gently to combine. Cut the reserved lemon slice in half, use these to garnish the drinks and serve warm.