Preheat the oven to 170C/150C Fan/Gas 3½. Lightly grease the pie dish with butter.
Gently heat the milk in a small saucepan. Add the lemon zest, butter and 2 tablespoons of the sugar and stir until the sugar is dissolved.
Lightly whisk the egg yolks in a bowl, then gradually pour in the warmed milk mixture, whisking continuously. Pour the mixture into a baking dish and gently stir in the breadcrumbs. Leave for 15 minutes so the breadcrumbs can soak up the liquid. Bake for 25–30 minutes, or until set. Remove from the oven and set aside to cool slightly.
Heat the jam and raspberries gently in a small saucepan until the raspberries break down, crushing them slightly with the back of a wooden spoon. Spread the jam mixture evenly over the base in the dish.
Increase the oven temperature to 190C/170C Fan/Gas 5. Whisk the egg whites using an electric hand whisk in a clean bowl until stiff peaks form. Gradually whisk in the remaining sugar until the mixture is stiff and glossy. Spoon the meringue over the jam, using the back of the spoon to spread the mixture over any gaps. Bake for 10–15 minutes, or until the meringue is crisp and golden. Serve immediately.