Steamed Mahi Mahi with Vegetables and Garlic Mustard Sauce

http://www.foodnetwork.com/recipes/sandra-lee/steamed-mahi-mahi-with-vegetables-and-garlic-mustard-sauce-recipe/index.html

Ingredients
1 teaspoon canola oil
1/2 red onion, sliced
1 medium yellow squash, sliced
1 medium zucchini, sliced
1/2 (8-ounce) package sliced mushrooms
1 cup chicken broth
Kosher salt and freshly ground black pepper
4 (4-ounce) pieces mahi mahi
4 sprigs fresh thyme
1 tablespoon chopped garlic
2 tablespoon spicy brown mustard

Directions
In a high-sided skillet over medium heat, add the canola oil. When it is hot toss in half the onion and cook until softened, about 5 minutes. Add the remaining squash and zucchini, mushrooms, and broth and season with salt and pepper. Place the fish on the vegetables and top each piece with a sprig of thyme. Season the fish with salt and pepper, cover, and steam until the fish is cooked through, about 10 minutes.

Remove the fish to a plate and cover to keep warm. Remove the vegetables with a slotted spoon to a bowl and cover to keep warm. Turn the heat to high and let the broth bubble, add the garlic and mustard and let cook until the sauce reduces and thickens, 3 to 5 minutes. Taste and add more salt and pepper, if needed.

Spoon the vegetables onto a plate and top with a piece of fish. Pour the sauce over the fish and serve.