Step 1

In large pot of boiling salted water, cook macaroni five minutes. Drain and rinse (macaroni will not be tender). In four-quart slow cooker, whisk together butter, flour, thyme, nutmeg, 1 1/2 teaspoon salt and 1/2 teaspoon pepper.

Step 2

Whisk in half-and-half, canned pumpkin, and Worcestershire sauce. Stir in macaroni and two cups sharp Cheddar cheese.

Step 3

Cover slow cooker; cook on low one hour until mixture is creamy and slightly thickened. Stir; sprinkle with remaining cheese. Cover; cook 45 minutes until cheese is melted and macaroni is tender. Garnish with pumpkin seeds and thyme sprigs, if desired.