In a saucepan, combine mirin, rice vinegar, miso paste, brown sugar, and soy sauce. Heat the mixture over medium heat for about 5 minutes, stirring constantly until everything is well blended and the sugar is dissolved.

Once combined, remove the saucepan from heat and strain the mixture through a fine-mesh sieve to eliminate any lumps. Allow the strained glaze to cool at room temperature for about 15 minutes.

Place the salmon fillets in a shallow dish and pour the cooled miso glaze over them. Cover the dish with plastic wrap and marinate in the refrigerator for at least 30 minutes.

In a large skillet, heat 2 tablespoons of sesame oil over medium heat. Add the finely chopped spring onions and crushed garlic, sautéing for about 2-3 minutes until fragrant.

To the sautéed aromatics, add 2 tablespoons of soy sauce, 1 tablespoon of rice vinegar, and 1 tablespoon of brown sugar, stirring well. Pour in ½ cup of water and let the mixture simmer for about 3-4 minutes.

Add the cooked noodles to the skillet, tossing them gently to coat with the sauce. Cook for another 2-3 minutes over low heat.

Preheat your oven to 220°C (430°F). This high temperature is crucial for achieving a beautifully caramelized exterior on your salmon.

Line a baking dish with parchment paper and arrange your marinated salmon fillets inside, skin side down. Bake for 7-10 minutes.

To serve, place a generous portion of garlic noodles on each plate and top with a piece of miso-glazed salmon. Garnish with sesame seeds, chopped coriander, and sliced chillies.