Preheat the oven to 200ºC/400ºF/gas ,

Put the butter, sugar and 1 teaspoon of sea salt in a pan with 325ml of water. Bring to the boil.,

Remove from the heat, add the flour and beat into a paste. Beat in the eggs, one by one, till smooth and combined.,

Transfer the mixture to a piping bag fitted with a plain nozzle.,

Pipe onto 2 large non-stick baking trays in dollops the size of large walnuts, leaving a gap between them so they can rise. You should get about ,

Wet your finger and gently squash the peak on each so they don’t burn, then bake for 15 to 20 minutes, or until puffed and golden.,

Remove from the oven and cool on a wire rack, then use a small sharp knife to pierce a little hole in each.,

Wash out the piping bag and nozzle, then spoon in the dulce de leche. Pipe the buns with dulce de leche, until just full. It might take a little practice, so don’t worry if you mess up a couple. Persevere, it’s worth it.,

If making the chocolate sauce, smash up the chocolate and place in a heatproof glass bowl with the cream and a pinch of salt.,

Place over a pan of gently simmering water (make sure the water doesn’t touch the bowl), and leave until the chocolate is melted and glossy, stirring occasionally.,

Make a toffee by adding the golden sugar to a shallow heavy-based non-stick pan with 50ml of water.,

Place over a high heat and leave to bubble for 4 to 5 minutes, or until light brown and syrupy. Don’t stir it, just gently shake the pan occasionally, and be careful – hot sugar can burn very easily, so keep the kids away and don’t be tempted to taste it.,

Leave the toffee for a few minutes to cool slightly, then, using tongs, carefully and lightly dip each bun into the toffee to get just a very thin coating (you don’t want to break your guests’ teeth) and practise sticking them together.,

Once you’re happy, arrange the buns on a platter so they stick together and build upwards into a pyramid shape. Serve with chocolate sauce, if you like.