Preheat the oven to 350F. In a large bowl, combine the flour, sugar, baking powder and salt. In a small bowl (or measuring cup) stir the milk, canola oil and egg together with a fork. Add the wet ingredients to the dry ingredients and stir until well combined. Pour into a buttered or sprayed 8 or 9 inch cake pan and bake for 25-30 minutes, or until golden and springy to the touch.
Get a bowl with an 8 or 9 inch opening at the top (depending on the size of cake you’re working with) and line it with plastic wrap. Spoon some cherry sorbet into the bottom of the bowl and press it down, smoothing the top. Spoon some mango overtop, making sure there are no air pockets and smoothing the top. Top with the cooled cake, cover and freeze for several hours, until solidified.
In the bowl of a double boiler (or a glass or stainless steel bowl that will fit over a saucepan of simmering water), whisk together the egg whites and sugar. Set over an inch or two of simmering water and whisk until the mixture is warm to the touch. Remove the bowl from the heat and beat with an electric mixer until stiff peaks form. If you want to broil the cake, preheat your broiler.
Remove the frozen cake and ice cream from the freezer, unwrap it on a serving plate and cover with meringue. Brown the surface with a culinary blowtorch or run it under the broiler for a minute or two, just until golden on the surface. Serve immediately. Serves 8-12.