This oven baked 4-ingredient cheddar and scallion macaroni is the kind of cozy, no-fuss dinner that feels like a hug at the end of a long day. I learned this simple, clever method from my Irish grandfather, who believed good food didn’t need a long ingredient list—just a little patience and plenty of cheese. Everything bakes together right in one glass casserole dish, and the result is golden, bubbly macaroni with a crispy top, sharp cheddar in every bite, and bright scallions sprinkled over for a fresh, oniony pop. It’s perfect for busy weeknights when you want something comforting that the whole family will actually eat.
Serve this cheddar and scallion macaroni straight from the glass casserole dish with a big green salad or simple steamed veggies to balance the richness. Buttered peas or green beans are especially nice, and a side of sliced tomatoes with a sprinkle of salt and pepper gives a fresh, juicy contrast. If you’re feeding a crowd, add some crusty bread for scooping up the cheesy edges, and maybe a bowl of fruit salad for dessert to keep the meal light but satisfying.
Oven Baked 4-Ingredient Cheddar and Scallion Macaroni
Servings: 4

Ingredients
2 cups uncooked elbow macaroni (about 8 ounces)
3 cups whole milk
3 cups shredded sharp cheddar cheese, divided
4 scallions, thinly sliced, divided
1 teaspoon kosher salt (optional, to taste)
1/2 teaspoon black pepper (optional, to taste)
Butter or oil for greasing the dish (optional, for easier cleanup)
Directions
Preheat your oven to 350°F (175°C). Lightly grease a glass 2-quart casserole dish with a little butter or oil so the macaroni doesn’t stick.
Spread the uncooked elbow macaroni evenly in the bottom of the casserole dish. Give the dish a gentle shake so the noodles settle into an even layer.
Pour the whole milk over the macaroni, making sure all the pasta is mostly submerged. It will look a little soupy at this stage—that’s exactly what you want so the noodles can absorb the liquid as they bake.
Stir in about half of the sliced scallions, tucking them down into the milk and pasta. This lets their flavor gently infuse the macaroni as it cooks.
Sprinkle 2 1/2 cups of the shredded sharp cheddar cheese evenly over the top of the milk and macaroni. Do not stir; you want a thick blanket of cheese that will melt down and help create a creamy sauce underneath.
Season the top lightly with salt and black pepper if using. Keep in mind that cheddar can be salty, so go easy and adjust next time based on your family’s taste.
Cover the casserole dish tightly with foil. Bake for 30 minutes, until the milk is hot and the pasta is starting to soften. If you peek, be careful of the steam when lifting the foil.
Remove the foil, give the macaroni a gentle stir from the edges toward the center to help distribute the melted cheese and make sure the noodles are all getting some sauce.
Sprinkle the remaining 1/2 cup of shredded cheddar over the top in an even layer. Return the dish to the oven, uncovered, and bake for another 20–25 minutes, or until the top is golden, the edges are bubbling, and the pasta is tender when you bite into a piece.
In the last 5 minutes of baking, scatter the remaining sliced scallions over the top so they stay bright green but still soften slightly in the heat.
Once the top is nicely browned and crispy in spots, remove the casserole from the oven and let it rest for 5–10 minutes. This short rest helps the sauce thicken up a bit so the macaroni scoops out in neat, cheesy spoonfuls.
Serve warm, making sure each portion gets some of the golden top, creamy center, and fresh scallions. Leftovers reheat well in the oven with a small splash of milk if needed to loosen the sauce.
Variations & Tips
For picky eaters, you can stir the scallions into just half of the dish before baking, leaving the other half plain and topped only with cheddar. If your family prefers a milder onion flavor, use fewer scallions or slice them very finely so they melt into the cheese more. Granddad’s version used sharp cheddar, but you can swap in an Irish cheddar for extra tang or a medium cheddar for a softer flavor. For a slightly firmer, drier top, bake an extra 5–10 minutes; for creamier macaroni, add an extra 1/2 cup of milk and check the pasta a few minutes early. If you like a little crunch, you can sprinkle a small handful of crushed crackers or plain bread crumbs over the final cheese layer before the last bake (this technically adds an ingredient, but it’s a nice touch for special occasions). To bulk it up, stir in leftover cooked ham or shredded chicken after the first 30 minutes of baking, then top with the remaining cheese and continue as directed. This dish also travels well—bake it in the glass casserole, cover, and take it to potlucks or drop-off dinners for friends who need a comforting, low-effort meal.