This is a simple, versatile dish that also works with other whole fish such as striped bass, red snapper or branzino. I happened to find smoked garlic at the produce market so decided to use it here. The extra layer of flavour is nice but don't worry if you can't find it; regular garlic is just as nice.
Yield: 6 servings as a main course
2 whole rainbow trout (each about 1 1/2 lbs), cleaned, scaled and gutted
1 lb new potatoes, cleaned and left unpeeled
3/4 lb cherry tomatoes
3 small yellow onions, peeled and cut into 1/2" slices
6 smoked (or regular) garlic cloves, unpeeled and crushed
6 fresh thyme sprigs
1 bay leaf
extra virgin olive oil
kosher salt and freshly ground black pepper
Preheat the oven to 350F. Place the potatoes, bay leaf and 1 teaspoon salt in a pot. Cover with cold water and parboil until almost tender. Drain and let cool enough so that you can handle them and cut into fourths. Toss the cooked potatoes, onions, garlic, and thyme sprigs in olive oil and season well with salt and black pepper. Arrange in a single layer on a sheet tray and roast for 20 minutes.
While the potatoes are roasting, prepare the fish by scoring 4-5 times on both sides, rubbing with extra virgin olive oil and season well with salt and freshly ground black pepper, inside the cavity and on the skin.
Place the fish on top of the potatoes and arrange the cherry tomatoes around it. Roast for 20 minutes until the flesh is cooked through, the potatoes are crisp, the onions are caramelised and the tomatoes are blistered.