Preheat the oven

• Preheat the oven to 200℃/380℉, fan forced.

  Tip - It helps to use an oven thermometer to know the exact temperature in the oven. Over a period of time, the settings in the oven can become slightly off than what the controller says.

Gather & prepare all the ingredients

• Peel & mince the garlic.
• Shred both the cheese. Measure & separate the portions needed for the sauce and for baking. Combine & mix the cheese reserved for baking.
• Measure & keep ready the butter, flour, milk & herbs/spices.
• Wash & roughly chop the parsley for garnish.
  

Cook the pasta

Time the cooking of the sauce & the pasta so that the sauce is ready before the pasta is cooked. This is preferable to waiting for the sauce to finish cooking as the residual heat can cause the pasta to become soft.

• Bring a large pot of water to a rolling boil.

  Tip - To speed up the process, use a kettle to heat the water and then add it to the pot.
• Add salt.
• Add the pasta & cook al dente as per packet instructions (approx. 7-9 minutes). It’s a good idea to start checking the pasta at least 2-3 minutes earlier than the time mentioned on the packet.

Make the sauce

• Meanwhile, melt butter in a heavy-bottom saucepan over low-medium heat.
• Add minced garlic and sauté briefly to remove the raw smell.
• Reduce the flame to low and stir in the plain flour using a spiral whisk.
• Initially the roux is a thick paste and will change consistency as it cooks. Continue whisking and cooking the roux until it reaches the desired consistency.
  
• You will know the roux is ready when it is bubbling gently & becomes loose (does not hold shape) as the flour will release the butter once it's cooked (approx. 2½ - 3 minutes). Follow the time provided as a rough guideline and add the milk based on the consistency of the roux.
  
• Once the roux reaches the desired consistency, gradually & slowly add the milk, whisking continuously to prevent lumps.
• Increase the heat to medium and add the mustard powder (or dijon mustard), dried mixed Italian herbs, ground white pepper, salt, and garlic powder (if using in place of fresh garlic).
• Mix until well combined and continue to stir. The sauce will start to thicken in approx. 2-3 minutes. Keep stirring until the sauce is thick & creamy and it starts to boil (approx. 5-7 minutes after adding the milk).
• To determine if the sauce has reached the desired consistency, coat the back of a spoon with the sauce and run your finger across it. If the path created by your finger remains clear and does not fill in, the sauce is ready. Do keep in mind that the sauce will continue to thicken after adding cheese & as it cools down.
  
• Taste & adjust seasoning if needed and turn off the heat.
• Stir in the ground nutmeg.
• Add shredded cheese and stir until fully melted and combined with the sauce.
  
• Gently fold in the cooked pasta until well coated with the sauce.
  

To bake

• Tip/spoon the pasta into a large enough ovenproof dish.
  
• Cover with shredded cheese.
  
• Place the pasta dish on the center rack and bake uncovered in the oven for a total of around 8-10 minutes. For the first 5 minutes (approximately), bake at a fan-forced setting to melt the cheese. Once the cheese has melted, adjust the knob to ‘fan-forced grill or top heat only’ to brown the cheese. Keep a close eye on the cheese (to avoid burning the cheese) and bake till the cheese is golden brown, approximately 3-5 minutes (depending on your oven settings).
• Once baked, take the dish out from the oven and let it rest for approx. 5 minutes.
• Garnish with fresh parsley.
  
• Serve as-is or with a side dish of your choice.