Lobster Mac and Cheese with Ritz Crumb Topping

Why You’ll Love This Recipe

• Silky, ultra-creamy cheddar–Gruyère sauce with a gentle kick of Old Bay and sherry.
• Sweet, tender butter-poached lobster in every bite.
• Buttery Ritz crumb topping that bakes up shatteringly crisp.
• Restaurant-worthy but written for home kitchens with clear, reliable steps.

Grocery List

• Produce: Garlic, fresh thyme (optional), chives or parsley, lemon (optional)
• Dairy: Unsalted butter, whole milk, sharp cheddar (block), Gruyère (block), Parmesan (optional)
• Pantry: Elbow macaroni, Ritz crackers, Old Bay seasoning, dry sherry, Dijon mustard, cayenne, kosher salt, white/black pepper, all-purpose flour, lobster meat (tails/claws)

Full Ingredients

Butter-Poached Lobster

• 1 lb lobster meat (from 2–3 tails or cooked claws/knuckles), cut into 1-inch pieces
• 1/2 cup (1 stick) unsalted butter
• 1/4 cup water (to start the beurre monté)
• 1 garlic clove, lightly smashed (optional)
• 1 small sprig fresh thyme (optional)
• Pinch kosher salt

Pasta

• 12 oz elbow macaroni
• Kosher salt for boiling water
• 1 tbsp unsalted butter or 1–2 tbsp reserved poaching butter

Cheddar–Gruyère Sauce

• 3 tbsp unsalted butter
• 3 tbsp all-purpose flour
• 3 cups whole milk, warmed
• 8 oz sharp cheddar, grated (about 2 cups packed)
• 4 oz Gruyère, grated (about 1 1/2 cups packed)
• Optional: reserve 1/2 cup combined cheeses for under the crumbs
• 2 tbsp dry sherry
• 2 tsp Old Bay seasoning
• 1 tsp Dijon mustard
• 1/4 tsp cayenne pepper
• 1/4 tsp white pepper
• 3/4 tsp kosher salt, plus more to taste
• Pinch ground nutmeg (optional)

Buttery Ritz Crumb Topping

• 1 1/2 cups Ritz crackers, lightly crushed (coarse crumbs)
• 4 tbsp unsalted butter, melted
• 2 tbsp finely grated Parmesan (optional)
• Pinch Old Bay and a few grinds black pepper

To Finish

• 2 tbsp finely chopped chives or parsley
• Lemon wedges for serving (optional)

Step-by-Step Instructions

Step 1: Preheat and Prep

Heat the oven to 350°F. Butter a 3-quart baking dish (9×13-inch). Warm the milk over low heat so it’s ready for the sauce. Grate the cheddar and Gruyère and, if you like, reserve 1/2 cup of the combined cheeses for a little melty layer under the crumbs. Lightly crush the Ritz crackers into coarse crumbs.

Step 2: Butter-Poach the Lobster

In a small saucepan, bring 1/4 cup water to a bare simmer over low heat. Whisk in 1/2 cup butter a few pieces at a time to form a creamy emulsified butter (beurre monté). Keep the poaching liquid at 160–180°F; add the smashed garlic, thyme, and a pinch of salt. Add lobster pieces and gently poach until just opaque and tender, 5–7 minutes (internal temp about 140°F). Lift lobster out with a slotted spoon and roughly chop into bite-size pieces if needed. Reserve 1–2 tablespoons of the poaching butter for the pasta or crumbs.

Step 3: Par-Cook the Pasta

Bring a large pot of well-salted water to a boil. Cook the macaroni until 1–2 minutes shy of al dente (typically 6–7 minutes). Drain well, then toss with 1 tablespoon butter or some of the reserved poaching butter to prevent sticking. Set aside.

Step 4: Make the Cheese Sauce

In a large pot, melt 3 tablespoons butter over medium heat. Whisk in 3 tablespoons flour and cook 1 minute to remove raw flour taste. Gradually whisk in the 3 cups warm milk until smooth. Simmer, whisking, until slightly thick and glossy, 4–5 minutes. Off the heat, whisk in the cheddar and Gruyère until fully melted and silky. Stir in 2 tablespoons sherry, 2 teaspoons Old Bay, Dijon, cayenne, white pepper, nutmeg (if using), and 3/4 teaspoon salt. Taste and adjust seasoning.

Step 5: Fold in Pasta and Lobster

Add the drained macaroni and the butter-poached lobster to the pot of sauce. Gently fold to coat every piece. The mixture should be creamy and slightly loose (it will thicken in the oven). If it seems too thick, splash in a tablespoon or two of warm milk.

Step 6: Assemble with Ritz Crumbs and Bake

Spoon the mac and cheese into the buttered baking dish. If you reserved cheese, sprinkle it evenly over the surface. In a bowl, combine the crushed Ritz crumbs, 4 tablespoons melted butter, Parmesan (if using), a pinch of Old Bay, and black pepper. Scatter the crumbs evenly over the top. Bake at 350°F for 15 minutes, then switch to broil and toast the top until deep golden and crisp, 1–2 minutes. Watch closely.

Step 7: Rest, Garnish, and Serve

Let the dish rest 5–10 minutes to set. Finish with chopped chives or parsley. Serve warm with lemon wedges on the side if you enjoy a bright squeeze over rich seafood. Enjoy the crackly top, velvety sauce, and tender lobster in every bite.

Pro Tips

• Grate cheese from blocks for the smoothest sauce; pre-shredded can be grainy.
• Keep the sauce slightly thinner than you think; pasta will absorb moisture as it bakes.
• Maintain butter-poaching temp at 160–180°F so the lobster stays tender, not rubbery.
• Salt the pasta water generously; it’s your best chance to season the noodles.
• For extra lobster flavor, whisk a tablespoon of the poaching butter into the cheese sauce.

Variations

• Chesapeake Style: Swap in 1/2 lb lump crab for part of the lobster and add lemon zest to the crumbs. Keep Old Bay at the full 2 teaspoons.
• Truffle Twist: Add 1/2–1 teaspoon white truffle oil to the finished sauce and use a mix of Gruyère and fontina.
• Spicy: Add 1/2 teaspoon smoked paprika and a pinch of red pepper flakes; finish with chopped scallions.

Storage & Make-Ahead

Refrigerate leftovers in an airtight container up to 2 days. Reheat covered at 325°F until hot (15–20 minutes), adding a splash of milk to loosen, then uncover and broil briefly to re-crisp the top. For make-ahead, you can poach the lobster and refrigerate it in its poaching butter up to 24 hours, and prepare the cheese sauce up to 2 days ahead (cool quickly, refrigerate, then rewarm gently with a splash of milk). Assemble just before baking. Freezing is not recommended; lobster can become tough and the sauce may separate.

Nutrition (per serving)

Approximate per serving (6 servings): 920 calories; 53 g fat; 68 g carbohydrates; 3 g fiber; 7 g sugar; 42 g protein; 980 mg sodium.