Here's how I made it:
For the pizza base - I used store bought frozen pie crust. After thawing for 1.5 hours, I pressed it into a 10 inch round baking pan and baked at 450 F for 10 mins.
For the pizza sauce - I made a custard sauce. For this, bring 1 cup milk to a boil. In the meanwhile, mix 3 tbsp custard pwd with 1/4 cup cold milk. Add this to the boiling mix. Keep stirring constantly on medium heat till thickens. Add 1/2 cup sugar or to taste and cook some more till the mixture resembles a thickish sauce. Take off heat and add 1 tsp vanilla essence and 1 tsp cardamom pwd. Chill this mixture well.
Pizza toppings - I used mangoes, strawberries and blueberries. Additional good choices would be apples, bananas, kiwis, rasberries, chikoo, grapes etc.
To assemble - spread the chilled custard sauce on the cooled pizza base, top with fruits. My daughter & her friends had a blast topping the pizza.
Slice and serve immediately or keep in the refrigerator until ready to serve.