Add the mascarpone cheese to a large mixing bowl. Pour in the condensed milk and whisk them together for about 1 minute until the mixture is completely smooth, creamy, and lump-free. Don't rush this step, any lumps here will carry through to the final filling.

In a separate clean bowl, whip the heavy cream with a hand mixer or stand mixer starting on medium speed, then increasing to high. Whip until stiff peaks form. When you lift the whisk, the cream should hold a firm peak without drooping. This is what gives the tiramisu its light, mousse-like texture so don't stop too early.

Scoop about ⅓ of the whipped cream into the mascarpone mixture and fold it in to loosen the base. Then add the remaining whipped cream in two additions, folding gently each time with a rubber spatula. Use slow, sweeping motions from the bottom of the bowl up and over. Stop as soon as it's combined, overmixing will deflate the cream and make your filling dense.

Arrange the dipped ladyfingers in a single snug layer across the bottom of your serving dish. If needed, break a few ladyfingers to fill any gaps.

Spoon half of the mango mascarpone filling over the ladyfinger layer. Use an offset spatula or the back of a spoon to spread it into an even, smooth layer all the way to the edges.

Add your second layer of dipped ladyfingers directly on top of the filling, pressing them down very gently so they sit flat.

Spoon the remaining filling over the second ladyfinger layer and smooth the top as evenly as possible. This is the surface everyone will see, so take your time here.

Cover the dish tightly with plastic wrap, pressing it gently against the surface of the filling to prevent a skin from forming. Refrigerate for at least 6 hours. Overnight is strongly recommended, the ladyfingers soften to a perfect custardy texture and the layers set up beautifully.

Just before serving, pour the remaining 1 cup of mango pulp over the top of the tiramisu and spread it gently into an even layer. Scatter the chopped fresh mango over the surface. Slice and serve immediately straight from the fridge.