We were home for the weekend, and originally, we had a packed schedule. But Max’s baseball doubleheader was canceled because a Nor’easter was rolling in. We knew we would be completely grounded, which meant it was the perfect time for family movies, family games, and getting creative in the kitchen while stuck inside on a very rainy day.
We wanted a fun and simple dinner last night, so Lori decided to make some delicious hamburgers. Normally, burgers call for standard French fries, but I was craving something a little different. We had some potatoes and yellow squash in the house, and I thought it might be fun to try and whip up some sort of gratin.
Instead of making a traditional scalloped potato dish loaded with heavy cream and butter, I wanted to do something a little bit more on the healthy side. When I want a rich sauce without relying on a ton of fat, I usually turn to my old friend: cornstarch. I did a little research, collected some ideas, and pieced together a simple recipe based entirely on ingredients I already had on hand. My goal was something incredibly tasty to accompany those burgers, but simple enough to throw together with what was already in the pantry.
Here is the recipe if you’d like to give it a try!
Lighter Rosemary Parmesan Potato & Squash Gratin
Equipment Options:
- A 9×9-inch ceramic/glass baking dish (with aluminum foil)
- OR a 3.5-quart Enameled Cast Iron Dutch oven (with its heavy lid)
The Ingredients
- 4 medium potatoes (peeled and sliced uniformly ⅛-inch thick)
- 2 large yellow squash (peeled and sliced uniformly ⅛-inch thick)
- 1 tablespoon butter
- 1 tablespoon dried rosemary
- 1 teaspoon onion powder
- ½ teaspoon salt
- ¼ teaspoon black pepper
- 1 cup chicken stock
- 2 tablespoons cornstarch (mixed with a splash of cold water to make a slurry)
- 2 tablespoons half-and-half
- Grated parmesan cheese (a generous amount for layering and topping)
The Instructions
1. Prep the Equipment & Veggies
- Preheat your oven to 400°F.
- Lightly grease the bottom and sides of your 9×9 baking dish or 3.5-quart Dutch oven (even if using enameled cast iron, this prevents the starches from sticking).
2. Build the Sauce Base
- In a small saucepan over medium heat, melt the 1 tablespoon of butter.
- Rub the 1 tablespoon of dried rosemary firmly between your palms to crush the leaves, then drop it into the melted butter along with the 1 teaspoon onion powder. Let the herbs sizzle gently for 30 to 60 seconds until fragrant.
- Pour in the 1 cup of chicken stock, add the ½ teaspoon salt and ¼ teaspoon pepper. Bring to a gentle simmer.
3. Thicken the Sauce
- Stir the cornstarch slurry into the simmering stock. Let it bubble for about 1 minute. Recipe Note: Using 2 tablespoons of cornstarch will create a very thick, almost pudding-like gravy on the stove. Once you whisk in the half-and-half (just before layering) it will loosen up a bit, and the natural juices from the squash will perfectly thin the sauce out while it bakes. Remove the pan from the heat.
4. The Layering Process
- Layer 1: Whisk your 2 tablespoons of half-and-half into the warm gravy. Arrange half of the sliced potatoes evenly across the bottom of your greased dish. Top with half of the sliced squash. Pour exactly half of your creamy rosemary sauce over the vegetables, and finish with a generous sprinkle of grated parmesan cheese.
- Layer 2: Repeat the exact same order—the remaining potatoes, the remaining squash, the remaining sauce, and a final generous layer of parmesan cheese on top.
5. Bake
- Cover and Steam (30–35 minutes): Cover your 9×9 dish tightly with foil, or place the heavy lid on your Dutch oven. Bake covered for 30 to 35 minutes to steam the potatoes perfectly tender.
- Crisp the Top (15–20 minutes): Remove the foil or the lid. Continue baking uncovered for another 15 to 20 minutes until bubbling and golden brown. Let the gratin rest for 5 to 10 minutes before scooping.
The Taste Test & Final Thoughts
Once dinner was ready and we all took our first bite, the verdict was unanimous—this one turned out really well! I will be the first to admit that it is not every time you create a recipe from scratch that it comes out perfectly on the first try. But every now and then, the magic does happen.
One of the biggest surprises was the texture. I initially wondered if a wet vegetable like squash and a starchy vegetable like a potato could really blend well while cooking in the exact same pot for the same amount of time. Miraculously, the squash almost blended right into the potatoes, making it seem like one consistent, comforting dish. You knew the squash was there, yet it all seamlessly went together.
As we were eating it, we even started brainstorming variations. If you wanted to make this a hearty main course, you could easily layer in some browned ground beef or ground turkey to turn it into an amazing, pasta-free casserole. Pro-tip: For an extra kick, right after the baking time is done, sprinkle a little extra parmesan on top and throw it under the broiler for 2 minutes for the ultimate crusty cheese finish!
Well, we have officially reached Sunday and made it through the first day of the Nor’easter, but the wind continues today along with the pouring rain. So, who knows what will come out of our kitchen this time!