Dissolve custard powder in 1 cup of cold milk. Bring 2 cups of milk to a boil on medium heat. Then add dissolved custard-milk mixture and sugar, stirring frequently. Cook over medium-low heat until thickens (about 11-12 minutes), stirring frequently. Remove from the heat and let the custard cool until it reaches room temperature.
Meanwhile, place fruit into a large bowl and toss together (or place them into individual dessert dishes). Pour custard mixture over the mixed fruit, refrigerate for 3-4 hours and serve.