To make the dressing: In a small bowl, whisk together the lemon juice, honey or sugar, chaat masala, red chili pepper, and salt.Place the fruit in a large bowl. Pour the dressing over the fruits and gently toss to combine, being careful not to mash the fruits. Refrigerate the chaat for at least 15 minutes to allow the flavors to meld, but no more than an hour to prevent it from getting mushy. Serve it garnished with some chopped mint leaves if desired.