Grilled Corn Chowder Recipe

1 tablespoon canola oil

1/2 cup white onion, chopped

1 teaspoon salt, divided

2 medium potatoes, peeled and cut into ½-inch cubes

4 cups grilled corn kernels, plus extra to garnish

1 tablespoon lemongrass (tanglad), finely chopped (white part only)

1 tablespooon bell pepper, finely chopped

3 tablespoons all-purpose flour

4 cups chicken stock

1 1/2 cups coconut milk (gata)