A Fresh Take on Stuffed Zucchini
August is when tomatoes finally taste the way tomatoes should and gardens seem to produce zucchini faster than anyone can use it. This recipe brings both together in a dinner that celebrates them rather than hiding them.
Fresh Roma tomatoes, onion, and garlic are roasted with Italian seasoning and balsamic vinegar until concentrated and lightly caramelized. They are then blended into a smooth sauce, poured back into the same casserole dish, and topped with zucchini boats filled with Italian sausage. Buttery Parmesan breadcrumbs give everything a crisp, golden finish.
A Dinner Made for August
Tomatoes and zucchini are available throughout much of the year, but late summer is when they are at their best. August tomatoes are naturally sweeter and fuller in flavor, while freshly picked zucchini is firm, tender, and less likely to have the oversized seeds found in zucchini left on the vine too long.
This is also the time of year when gardens and farmers’ markets have plenty of both. This recipe turns that seasonal abundance into a complete and satisfying dinner.
Why Roma Tomatoes Work So Well
Roma tomatoes contain more flesh and less watery juice than many slicing tomatoes, making them especially well suited for sauce.
Roasting concentrates their flavor while allowing the edges to caramelize. Onion and whole garlic cloves roast alongside them, while balsamic vinegar contributes a little acidity and depth. Once blended, the mixture becomes a fresh tomato sauce without needing to simmer on the stove.
The finished sauce should still taste like fresh August tomatoes—not like a heavy, long-cooked winter sauce.
Using the Same Casserole Dish
The tomatoes, onion, and garlic are roasted directly in the same 9×13-inch casserole dish used to bake the stuffed zucchini. I use my cast-iron casserole pan, but any oven-safe 9×13-inch baking dish will work.
After roasting, the tomato mixture is briefly transferred and blended. The smooth sauce then goes right back into the casserole dish, followed by the stuffed zucchini boats. This captures all the flavorful juices and browned bits left behind from roasting the tomatoes.
For blending, I use a wide-mouth half-gallon Mason jar. Its tall sides contain the sauce and prevent the immersion blender from splattering tomato sauce around the kitchen.
Removing Excess Moisture from Zucchini
Zucchini naturally contains a considerable amount of water. If the boats go directly into the casserole, that moisture can release as they bake and thin the roasted tomato sauce.
Lightly salting the hollowed zucchini before filling helps draw out some of that water. Place the salted zucchini cut-side down on a wire rack for 20–30 minutes, then blot it thoroughly before adding the sausage.
This step does not dry out the zucchini. It simply helps the boats remain firmer while protecting the consistency of the sauce underneath.
A Buttery Parmesan Finish
The breadcrumb topping is added during the final portion of baking so it can become crisp and golden without burning.
Melted butter helps the breadcrumbs brown evenly, while Parmesan adds a savory, salty finish. The contrast between the crisp topping, juicy sausage, tender zucchini, and smooth roasted tomato sauce is what makes these boats feel like a complete casserole rather than simply stuffed vegetables.
Serving the Zucchini Boats
Two zucchini boats make a generous dinner serving, especially when spooned with plenty of the roasted tomato sauce from the casserole.
They can be served alone or paired with a simple green salad, crusty bread, or a small portion of pasta. Any extra roasted tomato sauce can also be refrigerated for pasta, meatballs, eggs, or another vegetable dish.
This is the kind of recipe August produce deserves: fresh tomatoes transformed into sauce, zucchini made into the main course, and enough Italian sausage and Parmesan to make the whole thing satisfying.
Italian Sausage-Stuffed Zucchini Boats with Roasted Tomato Sauce
Equipment
Ingredients
Roasted Tomato Sauce
- 10 Roma tomatoes, about 2 pounds, quartered
- 1 medium onion, cut into chunks
- 5 cloves garlic, peeled
- 2 tbsp extra-virgin olive oil
- 2 tsp Italian seasoning
- 1 tsp kosher salt
- 1/2 tsp freshly ground pepper
- Pinch of crushed red pepper flakes
- 1 tbsp balsamic vinegar
Zucchini Boats
- 3-4 medium zucchini
- 1/2 tsp kosher salt
- 1 pound Italian sausage
Parmesan Breadcrumb Topping
- 1/2 cup breadcrumbs
- 1/3 cup finely grated Parmesan cheese
- 2 tbsp butter, melted
- Freshly ground pepper
Instructions
- Preheat the oven to 425°F.Arrange the Roma tomatoes, onion, and garlic in a 9×13-inch casserole dish. I use my 9×13-inch cast-iron casserole pan so I can roast the sauce ingredients and bake the stuffed zucchini in the same pan.Drizzle the tomatoes, onion, and garlic with the olive oil and balsamic vinegar. Sprinkle with the Italian seasoning, kosher salt, black pepper, and crushed red pepper, then toss until evenly coated.Roast for 35–45 minutes, stirring once, until the tomatoes have collapsed, the onion is tender, and the edges are lightly browned.While the tomatoes roast, cut the zucchini in half lengthwise. Use a spoon to scoop out the centers, leaving approximately a ¼-inch-thick shell around the sides and bottom.Sprinkle the hollowed zucchini lightly with kosher salt. Place the zucchini cut-side down on a wire rack set over a baking sheet or clean kitchen towel. Let sit for 20–30 minutes, then blot thoroughly to remove the released moisture.Let the roasted tomato mixture cool for about 5 minutes. Transfer the tomatoes, onion, garlic, and all the accumulated juices to a room-temperature, wide-mouth half-gallon Mason jar. I like using a half-gallon Mason jar with my immersion blender because the tall sides keep the sauce from splattering out. Blend until smooth.Reduce the oven temperature to 400°F.Pour approximately 2 cups of the roasted tomato sauce back into the same 9×13-inch casserole dish and spread it evenly across the bottom.Divide the uncooked Italian sausage evenly among the zucchini boats, filling them loosely without packing the meat too firmly. Arrange the filled zucchini boats over the tomato sauce.Spoon a small amount of the roasted tomato sauce over the sausage filling in each zucchini boat.Bake uncovered for 20 minutes.While the zucchini boats bake, combine the breadcrumbs, Parmesan, melted butter, and a few grinds of black pepper.Remove the casserole from the oven and sprinkle the breadcrumb mixture evenly over the stuffed zucchini.Return the casserole to the oven and bake for another 15–20 minutes, or until the zucchini is tender, the topping is golden, and the Italian sausage reaches an internal temperature of 160°F.Let the zucchini boats rest for 5 minutes before serving. Spoon additional roasted tomato sauce from the casserole dish around each boat.