In a small saucepan, heat the milk until lukewarm. Take off the heat and set aside.
In a bowl of a freestanding mixer fitted with paddle or hook attachment, mix together yeast and sugar (if you do not owe freestanding mixer, simply mix both in a large bowl). Pour the milk over yeast and sugar mix, stir gently and cover with clean kitchen towel. Let it sit for 5 minutes, the mixture will become frothy.
Add butter, egg, salt and flour and mix on low speed for 5 minutes. The dough will be very soft, but don't worry, it will come together later on. Using a wooden spoon or spatula, bring the dough together into a rough ball and transfer to clean, lightly greased large bowl. If the dough is super sticky/ too sticky to handle, add a little bit more flour, but only a small amount. Cover with cling film or clean kitchen towel and let it rise for 1-2 hours, or until it has doubled in size.
Line the baking tray with baking paper and set aside. Lightly flour the work surface, and transfer the dough onto it. Gently punch the dough to release the air from it. Divide the dough into 4 equal pieces. Use your hands to shape each piece it into rough circle, then use a rolling pin dusted in some flour, to roll each piece into a circle of 10-inch in diameter (don't worry if they are not perfectly round).
Transfer one dough circle into prepared baking tray lined with baking paper. This is your bottom layer. Spread 1 tbsp of the raspberry jam (or your filling of choice) over the surface. Layer the remaining dough circles and filling on top. The top layer will not have any filling on it, only 3 of the 4 circles will be topped with filling. Use your hands to stretch the dough layers, in case if they loose their shape.
Place a large dinner plate, similar in size on top of your dough layers, and using a sharp knife or a pizza cutter, cut around it, so you have an even, round circle. Remove any off-cuts. Place a small bowl or an upside down glass in a middle of your dough circle and make an indent. This is the centre of your star bread.
Next, using the pizza cutter or a sharp knife, cut 16 even strips (it's easier to slice it into 4, then each 4 in half, and each half into half again). Using both hands, grab two strips of the dough and twist them twice away from each other (the other way will also work), then press the both ends together to make a point. Your star bread should have 8 points.
Cover the shaped bread with clingfilm or kitchen foil and allow it to rest for 20 minutes. Meanwhile, preheat the oven to 175 C (160 C fan).
Lightly brush the star bread with eggwash and bake in the middle shelf of the oven for 25-30 minutes, or until golden brown on top. If it starts browning too much, cover it with some aluminium foil for the last 5-10 minutes of baking.
Remove from the oven and allow it to cool for 5 minutes. Dust with some icing sugar and enjoy while warm.
if you don't have plain flour, you can also use bread flour (strong flour). The texture will not be as soft and fluffy, but it will still taste delicious.
other fillings ideas: Nutella (heat it up slightly in a microwave or a bowl over a pan with simmering water so it has more spreadable consistency), butter and cinnamon sugar (spread 1 tbsp of soft butter on top of 3 of the circles, then sprinkle with mixture of caster sugar and cinnamon), your favourite jam or spread, mixed nuts, dried fruit, etc.
for savoury version, reduce the sugar in the dough ingredients to 15 g. Use your favourite pesto, tomato sauce, grated cheese and herbs for the filling.