Roasted Brussels Sprouts, Golden Mushrooms, Brown-Butter Sage & Toasted Walnuts
With autumn finally settling in, my imagination wandered away from the usual tomato-and-cheese lasagna and into the woods.
I started thinking about mushrooms. Those deep, earthy flavors that make me think of damp leaves, fallen logs, and wandering through the forest in autumn. Then came walnuts, sage, roasted garlic, and Brussels sprouts with those wonderful little caramelized edges. Before I knew it, I was imagining myself eating on a moss-covered tree stump in the woods.
With little frogs.
And gnomes.
And before long, I had a whole lasagna taking shape in my head.
I wanted something creamy and rich, with plenty of earthy flavors and a little crunch. So I made a roasted-garlic béchamel with Gruyère, Parmesan, and brown-butter sage, then layered it with golden mushrooms, roasted Brussels sprouts, ricotta, and pasta. A little lemon zest went into the ricotta to brighten things up, and toasted walnuts brought everything together.
That's one of the things I enjoy so much about seasonal cooking.
I spent a good part of the afternoon roasting vegetables, browning butter, making the sauce, and putting everything together. No rushing. Just enjoying the process and seeing how all those flavors developed.
And oh, that béchamel! The roasted garlic, Gruyère, and brown-butter sage were so good together that I could have happily eaten it with a spoon.
By the time the lasagna was finished, the kitchen smelled incredible.
Which brings me to my little photography problem.
Sometimes I make something that looks and smells so inviting that I have absolutely no interest in stopping to take pictures. I know I should, especially when I plan to share the recipe, but all I want to do is sit down and eat.
This was one of those meals.
I did manage a few photographs, but let's just say my enthusiasm for dinner was considerably greater than my enthusiasm for food photography.
We had crusty bread and a simple lemon arugula salad alongside the lasagna. The bright, peppery salad was exactly what all that creamy richness needed.
And the lasagna itself? Wonderful. Earthy mushrooms, sweet roasted Brussels sprouts, creamy layers of cheese and pasta, that nutty sage butter, and toasted walnuts scattered over the top.
It was everything I'd been imagining while I was putting it together.
Well, almost everything.
There were no actual frogs or gnomes at the table.
Autumn Woodland White Lasagna Recipe
Servings: Approximately 6 generous portions
Total time: Approximately 2–2½ hours
Diet: Vegetarian and egg-free when made with egg-free noodles and vegetarian cheeses
Ingredients
Roasted Vegetables
1 pound Brussels sprouts, trimmed and thinly sliced
1 pound cremini mushrooms, sliced
1 whole head garlic
2½ tablespoons olive oil, divided
1 tablespoon unsalted butter
1 teaspoon kosher salt, divided, or to taste
Freshly ground black pepper
Brown-Butter Sage
3 tablespoons unsalted butter
¼ teaspoon ground sage or 8-10 fresh sage leaves
Roasted-Garlic Gruyère Béchamel
4 tablespoons unsalted butter
¼ cup all-purpose flour
3 cups whole milk
4 ounces Gruyère, grated
2 ounces Parmesan, grated
1 whole head roasted garlic, prepared above
Prepared brown-butter sage
Small pinch freshly grated nutmeg
Salt and freshly ground black pepper, to taste
Ricotta Filling
15 ounces whole-milk ricotta
2 tablespoons chopped fresh parsley
1 teaspoon finely grated lemon zest
¼ teaspoon freshly ground black pepper
Small pinch salt
For Assembly
9 regular lasagna noodles, plus a couple extra in case of breakage
2 ounces additional Gruyère, grated
½ cup chopped toasted walnuts, divided
Instructions
1. Roast the Garlic
Preheat the oven or air fryer oven to 375°F.
Slice approximately ¼ inch off the top of the garlic head to expose the cloves. Drizzle with about 1 teaspoon olive oil and wrap securely in aluminum foil.
Roast for approximately 30–40 minutes, until the garlic is soft, fragrant, and golden.
Allow it to cool slightly, then squeeze the roasted cloves from their skins and mash into a smooth paste.
2. Roast the Brussels Sprouts
Increase the oven or air fryer temperature to 400°F.
Toss the thinly sliced Brussels sprouts with 1½ tablespoons olive oil, ½ teaspoon salt, and freshly ground black pepper.
Spread them in a relatively even layer on a roasting tray.
Roast for approximately 12–16 minutes, tossing halfway through, until tender with golden, caramelized edges.
Work in batches if necessary to avoid overcrowding.
Set aside.
3. Toast the Walnuts
Reduce the oven or air fryer temperature to 325°F.
Spread the chopped walnuts in a shallow baking pan and toast for approximately 4–6 minutes, checking frequently.
Remove when lightly golden and fragrant. Set aside.
4. Brown the Mushrooms
Heat the remaining olive oil in a large skillet over medium-high heat.
Add the sliced mushrooms, working in batches if necessary.
Allow them to cook undisturbed for several minutes before stirring. Continue cooking until their moisture evaporates and they develop deep golden-brown edges.
Add 1 tablespoon butter, the remaining ½ teaspoon salt, and freshly ground black pepper toward the end of cooking.
Transfer to a bowl and set aside.
5. Make the Brown-Butter Sage
In a skillet over medium-low heat, melt 3 tablespoons butter.
Continue cooking, swirling occasionally, until the butter foams and develops little amber-brown flecks with a warm, nutty aroma.
Immediately remove from the heat and stir in ¼ teaspoon ground sage.
Transfer to a heatproof bowl to prevent further browning.
6. Prepare the Roasted-Garlic Gruyère Béchamel
Melt 4 tablespoons butter in a saucepan over medium-low heat.
Whisk in the flour and cook for approximately 2 minutes, stirring constantly. The mixture should remain pale.
Gradually add the milk, whisking thoroughly after each addition until smooth.
Continue cooking for approximately 5–8 minutes, until the sauce thickens enough to coat the back of a spoon but remains pourable.
Remove from the heat.
Stir in the mashed roasted garlic, followed by the grated Gruyère and Parmesan, adding the cheeses gradually and stirring until melted.
Add the prepared brown-butter sage, a small pinch of nutmeg, and freshly ground black pepper.
Taste and adjust the salt.
The finished sauce should be silky, creamy, and rich with roasted garlic, nutty cheese, and fragrant sage.
7. Prepare the Ricotta Filling
In a medium bowl, combine the ricotta, chopped parsley, lemon zest, black pepper, and a small pinch of salt.
Stir until creamy and evenly mixed.
8. Cook the Lasagna Noodles
Bring a large pot of salted water to a boil.
Cook the lasagna noodles approximately 2 minutes less than the package directions, leaving them slightly firm.
Drain and lay them flat on a lightly oiled surface to prevent sticking.
9. Assemble the Lasagna
Use a baking dish large enough to accommodate three noodles side by side, or a suitable deep, oven-safe air fryer cooking vessel approved by its manufacturer.
Spread a thin layer of béchamel over the bottom.
First Layer
3 cooked lasagna noodles
Approximately one-third of the ricotta mixture
Half the browned mushrooms
Half the roasted Brussels sprouts
A layer of béchamel
Second Layer
3 lasagna noodles
Approximately one-third of the ricotta mixture
Remaining mushrooms
Remaining Brussels sprouts
¼ cup toasted walnuts
Another layer of béchamel
Final Layer
3 lasagna noodles
Remaining ricotta
Remaining béchamel
2 ounces grated Gruyère
Reserve the remaining toasted walnuts for serving.
10. Bake
Ninja air fryer oven: Select Bake at 325°F. Bake for approximately 30–35 minutes, checking after 20 minutes, until the lasagna is bubbling around the edges, heated through, and golden on top.
Conventional oven: Bake at 350°F for approximately 30–40 minutes, until bubbling and heated through. Cover loosely with foil if the cheese begins browning too quickly.
Allow the lasagna to rest for 10–15 minutes before serving.
Scatter the remaining toasted walnuts over the top just before serving to preserve their crunch.
What to Serve With Autumn Woodland Lasagna
This lasagna is rich and full of flavor, so I like keeping the accompaniments simple.
Lemon Arugula Salad
Ingredients
4 cups baby arugula
1½ tablespoons fresh lemon juice
2 tablespoons extra-virgin olive oil
A little finely grated lemon zest
Freshly ground black pepper
Pinch of salt
A few shavings of vegetarian Parmesan-style cheese
Instructions
Whisk together the lemon juice, olive oil, lemon zest, salt, and pepper.
Just before serving, toss lightly with the arugula and finish with the cheese shavings.
The fresh, peppery greens and bright lemon are a lovely contrast to the creamy lasagna.
