Preheat the oven to 200°C (400°F) and line a heavy-duty sheet pan with parchment paper.
In a small mixing bowl, emulsify the miso paste, chili garlic sauce, oil, sesame oil, honey, soy sauce, ginger, and garlic into a smooth glaze.
Toss the cubed squash with 50% of the prepared glaze on the sheet pan until evenly coated. Arrange in a single layer with sufficient headspace for airflow.
Roast the squash for 20 minutes, or until the edges begin to soften and develop Maillard browning.
Remove the pan from the oven. Shift the squash to the perimeter and place the salmon fillets in the center.
Apply the remaining 50% of the glaze to the top and sides of the salmon fillets using a pastry brush.
Return the pan to the oven and roast for an additional 10 to 12 minutes, depending on the thickness of the fillets, until the salmon reaches an internal temperature of 63°C (145°F).
Garnish the tray with sliced scallions and sesame seeds before service.