• Measure your ingredients on a scale: Bread flour (300g), Dry Yeast (6g), Sugar (35g), Salt (7g), Butter (35g), Milk (145g). Leave the butter and milk out at room temperature.
• Crack the egg into a bowl and beat it thoroughly. Set aside.
• Now, place a sift over a large mixing bowl. Put your bread flour through the sift. Gently tap it until all the flour gets sifted.
• Then make three holes into the flour (reference video). Place the dry yeast, sugar and salt into the separate holes. Then slightly cover each hole. Now place milk and the egg mixture into the flour. 
• Mix everything together with a spatula until it begins to clump into a dough. 
• Sprinkle some flour onto a table top. Place your dough on top. 
• Now roll up your sleeves: Knead the dough until it doesn't stick to your fingers (~5 minutes)
• Then add the room-temperature butter into the dough. Set a timer for 10 minutes. And knead the butter into the dough for the full 10 minutes. (Trust us, you will need the full 10 minutes!)
• Now dust a mixing bowl with some flour. Place your dough ball into the middle. Cover with saran wrap so it doesn't dry out. 
• Next, boil some water in a pot. Place the pot into your oven - on the bottom rack.  This will provide just enough residual heat. Add your mixing bowl with the dough on the top rack. Set a timer for 1 hour. In the meanwhile, lets make our topping...

Make topping

• Cube onion into small pieces. Place it into the mixing bowl.
• Open the can of sweet corn and drain it. Place equal amount of corn into the mixing bowl. 
• Squeeze 5 tablespoons (or to taste) of mayonnaise into the bowl. 
• Give everything a good thorough mix. Sprinkle a few shake of black pepper. Set it aside
• Now, bring a pot of water up to boil. Blanche your sausage in for 2 minutes. Drain and set aside.

Second Proofing

• After 1 hour in the oven, take the mixing bowl out of the oven. The dough should have risen. 
• Place the dough onto your table. Use your hands and tear off small pieces of the dough. Roll each piece into a ball. Each ball should be roughly 70 grams - use your scale. It should produce around 8 balls.
• After you make all 8, cover them with saran wrap or a kitchen towel. Let them rest for another 15 minutes. 
• In the meanwhile, place mayonnaise and ketchup into Ziploc bags. Snip-off a tiny hole at the end - to create two piping bags. 
• After 15 minutes, take each dough ball and flatten it out with a roller. Place a sausage in the middle. Pinch the dough around the sausage. Then roll them on the table or between your hands.
• Next, use a pair of scissors and cut the sausage - you want to cut all the way through the sausage but not through the dough. Then move each sausage pieces left and right to form a flat surface (reference video). Go slow on the first one - it gets easier as you do more!
• Place all the finished pieces onto a baking tray and place into the oven. Boil a pot of water again and place into the bottom rack of the oven. We will do the second (and final) proofing. Set a timer for 40 minutes! 
• After 40 minutes, take it out of the oven. Now, place a few scoops of the onion topping over the bread - right down the middle. Don't cover the sausages. Next, place a few handful of cheese over the top. Then place a few zig-zags of ketchup and mayonnaise over the top. Finish with a few shakes of dried parsley.
• Pre-heat your oven to 150C (300F). Once its hot, place the pieces in. Note: I think it's better to bake on a wire rack (rather than baking tray). Bake for 15-20 minutes! Remember to keep an eye on it, and cook loss or longer depending on the color. 
• Let it cool down and enjoy! Bon Appetit!