1. Preheat the oven to 190°C (375°F) with convection heat.
2. Slice the leek (white and green parts) and cube the carrot.
Remove the skin from the salmon and cut into approximately 1.5cm (0.6 inch) cubes (some stores also sell salmon "lardons").
3. In a frying pan:
Sauté the leek and carrot with 1 tablespoon of olive oil for 5 minutes.
Add the salmon, salt, and pepper.
Sauté everything for another 5 minutes.
4. In a non-stick saucepan: pour the coconut milk, margarine, flour, and curry.
Heat over medium heat, stirring constantly with a whisk, until thickened.
Reduce heat to low and stir in half of the cheese for 2 minutes.
5. Combine the contents of the frying pan and saucepan in a gratin dish, mixing well.
6. Sprinkle with breadcrumbs, thyme or rosemary, and the remaining cheese.
7. Place under the broiler for 5-10 minutes, until the top of the gratin is golden brown.
8. Remove from the oven and let cool for 2-3 minutes to avoid burning yourself ;)