Preheat oven to 400°F. Cook pasta according to package directions until 1 to 2 minutes shy of al dente.
Dice 4 tablespoons butter and place in large mixing bowl. Warm cream in small saucepan; cover to keep warm. Once pasta is cooked and drained, add to mixing bowl with butter and toss to coat well. Stir in warm cream and muenster until cheese starts to melt. Mix in salt and pepper to taste.
Pour mixture into buttered 2-quart casserole dish. In small bowl, melt remaining 1 tablespoon butter. Mix in cracker crumbs. Toss with fork to coat evenly with butter. Sprinkle bread crumb mixture evenly over pasta.
Bake until sauce is bubbling and topping turns golden brown, about 15-20 minutes.