1. Heat a large saucepan over medium heat. Add 1 tablespoon oil to pan; swirl to coat. Add tomatoes, garlic, and thyme; cover and simmer 30 minutes or until tomatoes are very tender. Remove pan from heat. Add salt; coarsely mash with a potato masher.
2. Bring a large saucepan of water to a boil; add half of kale. Cook 1 minute. Remove kale from pan with a slotted spoon; plunge into ice water. Repeat procedure with remaining kale. Drain and pat dry. Remove center rib from each kale leaf, leaving the leaf whole and uncut at leafy end.
3. Rinse and drain quinoa. Heat a medium saucepan over medium-high heat. Add remaining 1 tablespoon olive oil to pan; swirl to coat. Add onion to pan; sauté 5 minutes or until tender. Add quinoa; cook 2 minutes, stirring constantly. Add broth; bring to a boil. Cover, reduce heat, and simmer 15 minutes or until liquid is absorbed. Remove pan from heat; stir in 3 tablespoons walnuts.
4. Preheat oven to 375°.
5. Spread about 3/4 cup tomato sauce over bottom of an 11 x 7-inch glass or ceramic baking dish coated with cooking spray. Working with 1 kale leaf at a time, place about 1/4 cup quinoa mixture in center of leaf. Fold in edges of leaf; roll up, jelly-roll fashion. Repeat procedure with remaining kale leaves and quinoa mixture to form 12 rolls. Place rolls, seam sides down, in dish. Spoon remaining sauce over rolls. Cover and bake at 375° for 20 minutes. Sprinkle evenly with remaining walnuts and cheese. Bake, uncovered, for 5 minutes.