Step 1

Melt the butter in a large pot over medium heat. Stir in the onion, celery, corn, carrots, and sauté for 5-7 minutes until vegetables are mostly tender (they'll cook a bit more in the next steps).

Step 2

Add the mushrooms, if using, and cook for 3-4 minutes.

Step 3

Add the salt, curry powder, mustard powder, parsley, and ground black pepper, and cook until fragrant, 1-2 minutes.

Step 4

Add the flour and stir well. Cook for 1-2 minutes.

Step 5

Gradually pour in the chicken broth, stirring or whisking constantly. Bring the soup to a boil, reduce the heat to low and let simmer, while stirring, for 5-6 minutes, until it has thickened slightly.

Step 6

Add the cooked rice, almonds, chicken and half-and-half. Bring the soup to a gentle simmer and cook for 30-45 minutes, stirring occasionally to prevent sticking. Moderate the heat so the soup doesn't boil vigorously. It will thicken as it simmers.

Step 7

Serve immediately or keep warm over low heat until serving.