Save to Pinterest There's something about the smell of pesto hitting hot butter that makes you pause mid-conversation and just breathe it in. I discovered this dish on a Tuesday night when I had leftover pesto, a craving for mac and cheese, and absolutely no plan—which somehow turned into the most comforting casserole that's now requested at every gathering. The Italian herbiness cuts through the richness of the cream sauce in a way that feels both unexpected and inevitable, like the dish was always meant to exist this way.
I remember serving this at a casual dinner party where someone's mom was visiting from Italy, and I was genuinely nervous about the combination. Halfway through her first bite, she looked up with this knowing smile and said it tasted like a memory of traveling through the countryside with friends—which somehow meant everything coming from someone who grew up eating actual Italian food. That's when I realized this dish works because it respects both traditions without pretending to be something it's not.
Ingredients
- Elbow macaroni (400g): Short pasta holds onto the creamy sauce better than long shapes, and cooking it slightly under ensures it soaks up flavor during baking without turning mushy.
- Chicken breasts (2 large): Butterflying and cutting into bite-sized pieces speeds up cooking and lets the pesto coating reach every surface for maximum flavor impact.
- Basil pesto (3 tbsp for marinade, 2 tbsp for topping): This is your bridge between Italian and comfort food—use quality pesto if possible, or make your own if you have a food processor and spare basil.
- Unsalted butter (3 tbsp plus 2 tbsp melted): Unsalted lets you control the seasoning while building the roux, which is essential for a smooth sauce that doesn't break.
- All-purpose flour (3 tbsp): This thickens the cream sauce without making it gloppy—the key is whisking it into butter fully before adding liquid.
- Whole milk and heavy cream (2 cups milk, 1 cup cream): Warming the milk first prevents lumps and helps the roux incorporate smoothly into a silky sauce.
- Sharp cheddar, mozzarella, and parmesan (2 cups, 1 cup, plus 1 cup for topping): The sharp cheddar brings depth, mozzarella creates that stringy texture, and parmesan adds umami—together they're unstoppable.
- Garlic powder and nutmeg (1/2 tsp and 1/4 tsp): These aren't optional; they add warmth and complexity that makes people wonder what the secret ingredient is.
- Panko breadcrumbs (1 cup): Panko stays crispy longer than regular breadcrumbs, giving you that golden-toasted texture that makes the casserole special.
Instructions
- Heat your oven and prep the dish:
- Set the oven to 200°C and grease your baking dish thoroughly so the casserole slides out cleanly when you're ready to serve. A little butter on the sides makes a difference.
- Get the pasta cooking:
- Bring salted water to a rolling boil and add your pasta, but here's the move: cook it 2 minutes under package time. It seems early, but the casserole finishes the cooking process in the oven, and you want that tender texture, not soft.
- Marinate the chicken while pasta cooks:
- Butterfly your chicken breasts by laying your hand flat on top and slicing horizontally, then cut them into bite-sized pieces. Toss with pesto, olive oil, salt, and pepper, letting it sit while you finish other tasks—those 10 minutes make the flavor sink in.
- Sear the chicken until golden:
- Heat a large skillet over medium-high heat and let the pesto-chicken pieces sear for 5 to 6 minutes, listening for that sizzle and watching for color changes. You're not cooking it through completely because it will finish in the oven, so don't wait for white all the way through.
- Build the cheese sauce foundation:
- Melt butter in a saucepan over medium heat, whisk in flour, and cook for exactly 1 minute, stirring constantly. This removes the raw flour taste and creates a proper roux that'll thicken without lumps.
- Create a smooth, creamy sauce:
- Gradually pour in the warm milk and cream while whisking steadily, keeping the mixture moving so lumps can't form. It takes about 3 to 4 minutes for the sauce to thicken enough that it coats the back of a spoon.
- Melt in the cheese and seasonings:
- Lower the heat and stir in the cheddar, mozzarella, and parmesan one handful at a time, waiting for each to fully melt before adding more. Add garlic powder, nutmeg, salt, and pepper, tasting as you go—this is your moment to adjust flavors.
- Combine everything gently:
- In a large bowl, fold together the drained pasta, cheese sauce, and pesto chicken using a rubber spatula, being gentle so you don't break up the chicken pieces. You want swirls of everything throughout, not a homogeneous mixture.
- Transfer to the baking dish:
- Pour the whole mixture into your prepared dish and spread it evenly with the back of a spoon. Don't stress about perfection here—it'll settle while it bakes.
- Make the crispy topping:
- Mix panko breadcrumbs, melted butter, grated parmesan, and pesto in a small bowl until it resembles coarse sand. Sprinkle this evenly over the casserole so every bite gets a little crunch.
- Bake until bubbling and golden:
- Slide into the oven for 20 to 25 minutes, watching for the topping to turn golden brown and the edges to bubble up slightly. Let it rest for 5 to 10 minutes after coming out—this firms everything up and makes serving much cleaner.
Save to Pinterest My neighbor brought over her kid one afternoon while I was testing this recipe, and the child took one bite and went completely quiet—which anyone with kids knows is either very good or very bad. Turns out it was very good; he asked if I could make it every week, which was the highest compliment. That's when I realized this dish bridges the gap between what makes kids happy and what impresses adults, which is honestly the ultimate win.
Why Pesto Changes Everything
Mac and cheese is comfort, but pesto is adventure—and when they meet in one dish, something unexpected happens. The basil adds brightness that cuts through the cream in just the right way, and it stops the whole thing from feeling heavy even though it's packed with cheese and butter. I've tried this without pesto, and it's fine, but it's like watching a black-and-white movie when you could be watching it in color.
The Chicken Question
Some casseroles hide their proteins, but this one celebrates the chicken as a starring ingredient. By cutting it into small pieces and coating it heavily in pesto, you ensure every forkful has that herby, tender chicken mixed in rather than landing on an unexpected chunk. I've also rotisserie-chicken'd this version when I'm short on time, and it works beautifully—just shred it gently and toss with pesto before adding to the mix.
Casserole Wisdom and Quick Fixes
Casseroles are forgiving, but they reward small attentions to detail. The difference between a sad casserole and a memorable one is often just in the topping—those breadcrumbs add texture contrast that your mouth actually notices. This dish can be assembled hours ahead, covered with plastic wrap, and baked when you're ready, which makes it perfect for that dinner party where you want to seem calm while actually being organized.
- If your topping isn't browning enough by minute 20, boost the oven to 220°C for the last 5 minutes to get that golden color without overcooking the interior.
- Leftover casserole reheats perfectly in a 180°C oven for about 15 minutes covered, then 5 minutes uncovered to crisp the top back up.
- Make sure your baking dish actually fits in your oven before you've mixed everything together—it's a small detail that prevents disaster.
Save to Pinterest This is the casserole I make when I want to feel like I've cooked something real but also want everyone at the table to be genuinely happy. There's comfort in that.
Questions & Answers
- → Can I use rotisserie chicken instead of raw chicken breasts?
Yes, simply shred a rotisserie chicken and toss with 3 tablespoons pesto before adding to the pasta mixture. This cuts preparation time significantly while maintaining great flavor.
- → What pasta shapes work best for this dish?
Elbow macaroni is traditional, but any short pasta like cavatappi, penne, or fusilli works well. The curves and ridges help hold the creamy cheese sauce and pesto flavors.
- → How do I prevent the sauce from becoming grainy?
Use room-temperature ingredients, warm your milk slightly before adding, and stir constantly over medium heat. Avoid high heat which can cause cheese to separate and become grainy.
- → Can I assemble this ahead of time?
Assemble everything up to step 8, cover tightly, and refrigerate up to 24 hours. Add the breadcrumb topping just before baking, and increase baking time by 10-15 minutes if baking from cold.
- → What wine pairs well with this casserole?
A chilled Sauvignon Blanc cuts through the richness beautifully. For red wine lovers, a light Pinot Noir or Chianti complements the Italian-inspired pesto elements without overpowering the dish.
- → How should I store leftovers?
Store in an airtight container in the refrigerator for 3-4 days. Reheat in the oven at 180°C (350°F) covered with foil until warmed through, about 20 minutes, to maintain the creamy texture.