- Add parsnips to large saucepan of boiling salted water. Cook 5 to 6 min until fork-tender. Drain well.
- Meanwhile, grease 13 X 9-in. (3-L) baking dish. Set aside. In large high-sided skillet or saucepan over medium heat, melt 3 tbsp (45 mL) butter. Add leeks, garlic, thyme, salt and pepper; cook 5 min. until leeks are softened. Stir in flour; cook 2 to 3 min. Gradually whisk in milk and saffron until sauce is smooth. Continue whisking sauce while bringing to a boil. Stir in parsnips. Reduce heat to medium-low. Cook 6 to 7 min. until sauce is thickened.
- Scrape into baking dish. (Make-Ahead: Cool parsnip mixture in baking dish; cover; keep chilled up to 1 day before proceeding with recipe.) Preheat oven to 375°F (190°C). Cover baking dish with foil, bake about 20 min., or until heated through.
- Mix breadcrumbs, cheese and chives (Make-Ahead: Mix breadcrumb mixture 1 day ahead; cover, keep chilled until ready to use). Sprinkle on baked parsnip mixture; dot with remaining 1 tbsp (15 mL) butter. Broil 2 min. until topping is golden brown and crisp. Let stand 10 min. before serving.
Homemade breadcrumbs can be made by pulsing day-old bread in a food processor until the texture of coarse meal. Freeze up to 1 month in a re-sealable plastic bag.