Preheat the oven to 400°F. In a shallow roasting pan, combine the sweet potato and onion. Sprinkle with salt and pepper; drizzle with 1 Tbsp. olive oil; toss to coat. Bake for 30 minutes until the vegetables are tender and lightly browned.
On another baking sheet (I line with parchment paper), add the salmon filets. Rub with 1 Tbsp. olive oil; season with salt and pepper and sprinkle with ginger. Bake at 400°F for 15-18 minutes.
Use a spiral slicer (spiralizer) or julienne peeler to cut the zucchini lengthwise into long, thin noodles (or use a regular vegetable peeler to cut the zucchini lengthwise into thin ribbons).
In a large skillet, heat the remaining 2 Tbsp. olive oil over medium-high heat. Add the zucchini, and the remaining garlic; cook, tossing gently with tongs, until the noodles are crisp-tender, 1 to 2 minutes. Add in the cabbage and cook for another 2-3 minutes.
Add the coconut milk and broth. Bring just to a boil, stirring frequently. Remove from the heat. Stir in the sweet potato mixture.
To serve, divide the zucchini mixture into 4 shallow serving bowls. Top with salmon. Sprinkle with the cilantro and mint. (You can also serve it in one big pot, as photo shows.)