- Brush bottom and sides of slow cooker insert (4.5 to 6 L capacity) with 1 tbsp (15 mL) butter. Add 1 cup (250 mL) milk. Gradually whisk in the cornstarch until smooth. Whisk in remaining milk and mustard. Stir in garlic, thyme, salt and pepper. Stir in macaroni.
- Cover and cook on HIGH 1 hr. 30 min., stirring once halfway through, or until macaroni is tender and sauce is thickened. Stir in cheese. Adjust setting to WARM for serving.
- Meanwhile, melt remaining butter in skillet over medium heat. Stir in breadcrumbs. Cook, stirring, 3 to 5 min. until breadcrumbs turn golden. Transfer to serving bowl. Stir in parsley.
- Scoop mac and cheese onto serving dishes. Sprinkle with breadcrumbs just before serving.
To make fresh breadcrumbs, cube stale bread and pulse in food processor to coarse crumbs.