Use store-bought pesto.
Spray a 9 X 12-inch baking dish with olive oil cooking spray. Preheat the oven to 350°F. Spray a large sauté pan with olive oil cooking spray and heat over high heat. Add the onions, mushrooms, asparagus and remaining 1 1/2 teaspoons garlic and sauté for five minutes, or until tender yet firm. Stir in the vinegar and stock. Spread the vegetable mixture in the baking dish and layer the fish on top. Spread the fish with the pesto. Bake for 12 to 15 minutes or until the fish is firm to the touch. Divide the Cauliflower mash on 2 plates and top with vegetables and fish. Have apple for dessert.