Preheat the oven to 220°C. Place the milk, sugar, salt and butter in a heavy-based saucepan. Heat over a medium heat until melted. Add the sifted flour in and whisk until smooth. Lower the heat and beat the mixture for 4-5 minutes. When the mixture starts to form a smooth ball and comes away from the sides of the saucepan, beat in the eggs in batches until smooth. Spoon the choux pastry into a piping bag fitted with a straight-sided nozzle (5cm in diameter). Grease and line baking sheets; pipe the balls of the pastry onto the sheet roughly 5cm in diameter. Bake for 20-25 minutes until golden-brown and hollow inside. Transfer to a wire rack to cool completely. Meanwhile, whip together the cream, icing sugar and vanilla extract until it forms soft peaks. Transfer to a clean piping bag, fitted with a straight-sided nozzle (4cm in diameter) and chill. Place the chocolate in a heatproof bowl and set above a pan of barely simmering water until melted. Remove from the heat and stir to make sure it's smooth. Halve the choux buns and pipe the cream into them. Stack the buns on a serving platter and drizzle the melted chocolate over the buns. Sprinkle the toasted almonds over and serve immediately.