Put fruit in a colander and wash under running water, tossing with your hands until clean and water runs clear. Fruit must be cleaned thoroughly or jelly will become cloudy. Drain well.
Put sugar and 2 cups water in a medium saucepan over a low heat. Cook, stirring, until sugar dissolves and mixture comes to the boil. Increase heat to medium, add fruit and cook for 10 mins. Drain fruit in a large sieve over a bowl, reserving liquid. Line a fine sieve with muslin. Put over bowl and strain liquid, reserving liquid.
Put fruit and reserved strained liquid in a large bowl. Put ½ cup water and gelatine in a microwave jug and whisk to combine. Stand for 5 mins or until gelatine is softened. Microwave on high/100% for 30-40 seconds or until gelatine is dissolved. Set aside to cool slightly, then stir into fruit mixture. Add ginger beer, brandy and lemon juice, and stir to combine. Pour into a wet 5-cup capacity jelly mould. Cover and refrigerate for 4-5 hrs, preferably overnight, or until set.
Carefully turn out jelly onto a platter or cake stand. Serve.